View Full Version : ESE's works engine tuner
MotleyCrue
17th December 2015, 14:24
Looking at the Lambda on the dyno they have a really linear A/F ratio, a Mik or Keihin is all over the place as the circuits overlap.
I have heard people say the opposite about Lectrons but no doubt they never had a Lambda sensor on their engines, probably never even had a Lectron on their engine either. Thanks for all the Lectron info.
J.A.W.
17th December 2015, 15:02
Interesting, everytime I see anything on the internet about FBG its always to do with big powerful 4 cylinder 4 strokes. To be honest I never heard of an H2 and never clicked on the H-2 tab on the FBG site before.
Yeah, Paul Gast still sponsors them big ol' 2Ts in drag racing comps.. see here..
www.cycledrag.com/long-live-the-two-strokes-garrett-wood-sets-super-eliminator-record-in-memphis
wobbly
17th December 2015, 15:13
One last point about the Lectron is that as it has no idle circuit in front of the slide, it can be run at a very steep downdraft angle to straighten out the
flow into the reedblock.
This is worth plenty of Hp.
If you sat a Mik or Kehin at those angles they would spew fuel from the bowl directly thru the idle circuit ( not having it drawn up thru the jet well by vacuum )
especially with the fuel surging to the front of the bowl under brakes.
TZ350
17th December 2015, 15:37
317983 317984
The Dam Question!
Chambers has fitted an exhaust port dam to his RG50 cylinder. It was hand shaped out of alloy and is held in place with a screw and sealed with Balzona epoxy.
We hope to get to test it on the dyno in the next night or two.
The top of the exhaust port is 85% wide and the dam fills the lower part of the original exhaust port and tapers out to the pipe diameter at the end of the exhaust duct.
J.A.W.
17th December 2015, 15:58
317983 317984
The Dam Question!
Chambers has fitted an exhaust port dam to his RG50 cylinder. It was hand shaped out of alloy and is held in place with a screw and sealed with Balzona epoxy.
We hope to get to test it on the dyno in the next night or two.
The top of the exhaust port is 85% wide and the dam fills the lower part of the original exhaust port and tapers out to the pipe diameter at the end of the exhaust duct.
Cool, & so - how long do you reckon on it lasting at WFO 'til the epoxy burns off, the exhaust pulse loosens the screw & it gets blown out?
If it does show a dyno-measured improvement, will you then weld it in?
Or, re-configure it - as a moveable 'power-valve' type set up?
crbbt
17th December 2015, 15:59
just wondering what the octane rating of the avgas you were running in that TZ Wob?
also I've been meaning to ask about ATAC chambers. can any valve be used? or does it have to be a butterfly valve to direct the flow into the chamber?
wobbly
17th December 2015, 18:30
The fuel is 100 Avgas,its higher octane than what is sold in OZ that is LL100.
The ATAC does not need to "direct " the flow, as I have always used the butterfly so that when its open its in line with the header axis.
husaberg
17th December 2015, 18:37
just wondering what the octane rating of the avgas you were running in that TZ Wob?
also I've been meaning to ask about ATAC chambers. can any valve be used? or does it have to be a butterfly valve to direct the flow into the chamber?
The fuel is 100 Avgas,its higher octane than what is sold in OZ that is LL100.
The ATAC does not need to "direct " the flow, as I have always used the butterfly so that when its open its in line with the header axis.
http://www.kiwibiker.co.nz/forums/search.php?searchid=10893793
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page367?p=1130203014#post1130203014
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130357926#post1130357926
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130341485#post1130341485
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130327391#post1130327391
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130327475#post1130327475
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130330857&highlight=atac#post1130330857
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130357767#post1130357767
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130357807#post1130357807
crbbt
17th December 2015, 20:57
Thanks for your response!
AndreasL
18th December 2015, 09:28
wobbly, a EngMod question if you don't mind...
When designing a exhaust duct using EngMod, I think it's ExMach that should be used to check if we go sonic or not?
ExPMach, measured at the port(?), goes through the roof (>3) when the port opens so that can't be the right thing to use...
So what I'm planing is to reduce my exduct end area untill we are about to kiss sonic.
Can it be that simple really? Probably not...
Using ExMach, do we like to place our virtual transducer att the smallest cross section area of the duct, i.e. just before the header (if not using some sort of adapter/spigot that is). Normally I run it at 0mm but that might not be the best thing in this case?
Do you have a graph from "a decent engine" showing what to look for regarding exhaust duct speed?
Now, lets see how wrong I am... :corn:
adegnes
18th December 2015, 09:48
So what I'm planing is to reduce my exduct end area untill we are about to kiss sonic.
Can it be that simple really? Probably not...
Interesting "thesis"!
AndreasL
18th December 2015, 10:27
Interesting "thesis"!
I'm running some rough sims right now and we are getting closer to sonic when makin the duct area smaller...as expected.
But with a single port, we might push it to far using this crude "technique"...
wobbly
18th December 2015, 11:46
Here is a KTM250 for road racing I have worked on.
This isnt anywhere near "full noise " as it needs powerband width to cope with a 1500 rpm drop into 5th gear.
The Ex port at the face goes well sonic as the piston opens and closes - so the lifted floor has nothing to do with flow velocity, its all to do with A port short circuiting.
I am going to try a big radius on just the floor of a lifted port to see if it raises power by increasing the outflow Cd, without affecting the short circuit reduction down the sides
where the corner rads are.
The transducer is set at the smallest area in the duct ( the cylinder face ) before the oval/round transition spigot, and this gave the best power - going smaller did not gain any power.
Going bigger did loose immediately, and it seems that in many engines going to around 0.8Mach at the exit seems to work best..
The stinger venturi just goes sonic for a short period, but again, this was the smallest area for best overall power without deto.
I could go bigger, and then i would need to add timing or increase com to compensate to lift the TuB number- and this lost band width.
As I have stated a hundred times the 75% area at the oval face will get you close every time, as will the 90% area for a single port.
Just remember that the sim will reduce the volume of the duct in a linear fashion, as you neck down the exit area, and this is the correct approach - not just weld up the last 20mm
as its easy to get at.
Also the sim has no idea there is a wall in front of the piston at BDC if you lift the port floor.
It cannot therefore adjust for any improved scavenging or trapping efficiency due to reducing the A port short circuiting - all its doing is reflecting the affect on in and outflow from
a smaller port/duct exit.
PS - what is a "rough " sim.
TZ350
18th December 2015, 16:25
317346
Chambers RG50 with a push and go ignition made by rewinding a race stater from a Loncin Race ignition for 12V to power the Ignitec. The Loncin rotor has a RG50 center bolted into it.
317342
The cylinder was modified for full reeds, a boost port and Boyesen like ports that got through to the top of the B transfers.
317343
The setup was run with two stage glass fiber reeds (Blue line) and heavier carbon fiber reeds (Red line).
317341
Then to see if the Boyesen like ports were doing anything worth while they were blocked off (Red line). Lost a bunch of top end but picked up some useful drive coming onto the pipe.
317345
Then the open duct between the boost port and B transfer ports was closed off (Red line).
317344
Blue, first run, Boyesen and Boost Duct open. Red Boyesen closed. Green, Boysens blocked plus Boost and B Transfers blocked off from each other.
The next move will be to keep the opening between the Boost and B Transfers blocked off and open the Boyesen like ducts up again.
The ambition is to run an RG50 and go better than 15 rwhp with it.
The last couple of weeks has all been about proving everything one step at a time..... After 160 plus runs the 85% width exhaust port is holding up well. so getting there bit by bit :niceone: and lots more things to try, like an exhaust port floor dam and a new 14K+ rpm pipe.
317983 317984
The Dam Question!
Chambers has fitted an exhaust port dam to his RG50 cylinder. It was hand shaped out of alloy and is held in place with a screw and sealed with Balzona epoxy.
We hope to get to test it on the dyno in the next night or two.
The top of the exhaust port is 85% wide and the dam fills the lower part of the original exhaust port and tapers out to the pipe diameter at the end of the exhaust duct.
317998
Red line is with the exhaust port dam, no other changes.
318000
Blue 95mj, Red 85mj, Green 105mj
317999
Blue is where we started at the very beginning and after a lot of hard work and careful step wise development we have worked our way to the Red line. ....... :facepalm:
peewee
18th December 2015, 18:14
we have worked our way to the Red line. ....... :facepalm:
but your dam went all the way to the transfer tops or no ? that what it appears from the photo. how tall was dam at blue line ?
F5 Dave
18th December 2015, 19:05
Glad its not just me Rob, but I feel your pain. Dynos suck when they show up what must work as doesn't.
TZ350
18th December 2015, 19:47
Glad its not just me Rob, but I feel your pain.
Getting used to the pain because things always seem to go backwards before getting it right. ... :laugh:
But it does leave me I a bit concerned about the dry sump gear box idea and extra large crankcase volume ....
318002318003
but your dam went all the way to the transfer tops or no ? that is what it appears from the photo. how tall was dam at blue line ?
Blue = no dam. Red = exhaust dam level with the transfer tops.
I think the Aprilia had a CNC machined exhaust port. They started low and progressively raised it finding more power with each step but they ran out of time before getting level with the transfer tops.
For practical reasons Chambers had to start high and now can progressively work down.
Lets see what tomorrow brings. ... :niceone:
husaberg
18th December 2015, 19:56
Blue = no dam. Red = exhaust dam level with the transfer tops.
I think the Aprilia had a CNC machined exhaust port. They started low and progressively raised it finding more power with each step but they ran out of time before getting level with the transfer tops.
For practical reasons Chambers had to start high and now can progressively work down.
Lets see what tomorrow brings. ... :niceone:
I know its Daves job but I couldn't resist.
I predict tomorrow will bring
<iframe width="560" height="315" src="https://www.youtube.com/embed/w5Fgp-KihIA" frameborder="0" allowfullscreen></iframe>
one of the pics I seen of the RSA duct seemed to have cuts overlapping for antibackflow but it might have been the angle or a quirk on the machining pattern.
Maybe Frits could confirm or deny the existence of this sort of datail?
wobbly
18th December 2015, 20:11
Keep in mind that my take on this is that the major effect is upon the A port short circuiting factor.
If you look at ducts that have had the floor lifted alot the bulk flow goes sonic quite severely, and this I feel can override the positive effect of the A port trapping efficiency.
Try lowering the floor but leave as much infill in the bottom corners as you can.
And at some stage try the big radius on the floor port corner only, as this will increase the outflow Cd but wont influence the trapping efficiency of the corners on the bad A port flow turning.
The Aprilia ducts were CNC cut, and what you are seeing is called steppover, ie the amount the cutter is advanced into the port for each successive tool path.
Another issue is that the added in dam has a crap heat transfer coefficient, and thus will be overheating the retained charge in the duct.
TZ350
18th December 2015, 20:26
If you look at ducts that have had the floor lifted a lot the bulk flow goes sonic quite severely, and this I feel can override the positive effect of the A port trapping efficiency.
Try lowering the floor but leave as much infill in the bottom corners as you can.
Thanks, yes instead of lowering it evenly across the port like we were going to, I will suggest to Chambers we take it down in more of a V shape.
Frits Overmars
19th December 2015, 01:15
one of the pics I seen of the RSA duct seemed to have cuts overlapping for antibackflow but it might have been the angle or a quirk on the machining pattern. Maybe Frits could confirm or deny the existence of this sort of datail?That's new to me, Husa. But I'll show you some pictures of the RSA exhaust duct if you show me yours.
318004 318005
peewee
19th December 2015, 06:18
hey wob a few questions on the yami twin. i got the straight cut primaries and it uses what appears to be a brass bushing between the basket and trans shaft. every other engine ive seen uses a double roller needle bearing. i may be able to swap the small gear in the center of the basket so i can then use a double needle bearing. would that be a good idea or just leave the brass bushing ?
on the oem ignition lighting coil. does it have enough power to run a small rad fan like whats used on the ktm dirtbikes ? service manual doesnt say anything about how many amps it is. just wondering if it would take more power to run the fan than i would see from a possible gain in lower water temp if that makes sense. if it takes 2hp to run the fan and ill only recover 1hp from the lower water temp is what im getting at
AndreasL
19th December 2015, 06:52
Thanks wobbly.
I have used the "75/90%"-rule so far. This was an attempt to try to make it a bit more scientific.
Guess trying some runs at those %, plus minus some, to optimize the duct/power curve is the way to go.
husaberg
19th December 2015, 07:55
That's new to me, Husa. But I'll show you some pictures of the RSA exhaust duct if you show me yours.
yours
318004 318005
From memory I tidied the pic up and made it super large as its very low resolution.
This is the low res version.
318011
Likely a trick of light or as Wob said overlapping cuts producing a pattern (much like engine turning)
I think the pic shows a progression in the raised corners at the lower ex duct it also shows the compromise made to the transfers to accommodate the ex and vice versa
318012
wobbly
19th December 2015, 08:51
Hey TeeZee, as a favour can you try a radius on the leading edge of floor dam, before you do anything else.
Be interesting to see if that helps the outflow Cd sufficiently to increase power, and wont affect the A port short circuiting efficiency at all.
Re the Yam twin, several models used the bronze bush with oil dimples in the loaded surface.
This works fine as its only actually being used as a bearing when the clutch is pulled in - the rest of the time its just a spacer bush.
The ignition lighting coil should have plenty of power for a fan, as its designed for powering a head and tail light etc
TZ350
19th December 2015, 09:28
Hey TeeZee, as a favor can you try a radius on the leading edge of floor dam, before you do anything else.
Be interesting to see if that helps the outflow Cd sufficiently to increase power, and wont affect the A port short circuiting efficiency at all.
Sure, Chambers thinks it looks like a good idea .... probably get to test it next Wednesday.
J.A.W.
19th December 2015, 11:02
The fuel is 100 Avgas,its higher octane than what is sold in OZ that is LL100.
The ATAC does not need to "direct " the flow, as I have always used the butterfly so that when its open its in line with the header axis.
It has been most interesting to see what you've achieved in successfully updating the TZ twin for classic racing, Wobbly.
I note that a decent sized contingent of US TZ riding classic racers are taking their 4 cyl jobs to Phillip.Is. next month..
www.cycleworld.com/2015/12/15/ienatsch-tuesday-vintage-motorcycle-fever-phillip-island-amcn-classic-vintage-race/
Are any of them applying your TZ development lessons - to give those huge Suzuki 4Ts - a run for their money?
wobbly
19th December 2015, 12:51
I met all the USA guys at the Island last year, a great bunch of really enthusiastic racers and tuners.
The TZ400 we took was easily fastest in practice, but the brand new Nova special ratio set shat 3rd gear in the morning warmup and threw Discombe down the road on his head.
He had concussion so wasnt allowed back on the bike.
Dennis Charlett is racing the Nationals at Timaru the weekend of the Island this year,so we will have to wait.
He is entered on the TZ for the last round at Hampton in early March,in the support Post Classic class, hope the new track is all done for that.
We wanted to run the Pre 82 in Superlight,as with a speedshifter working and stickys the TZ would easily cut lap times to be at the front, but the classes are too close together
for the Grandfather to be comfortable racing the SV650 as well.
Master plan is to build another Frepin with a 4 cylinder version of the TZ400, as Paul Mclachlan rode one configured like that at Puke with a std TZ500 back in the day.
If I put the same attention to detail into that bike it will for sure easily smoke the usual 750s as well as the big 4T pigs at the Island, we will see.
Here is another small item in the TZ400 - a double sized CNC waterpump impeller,it sits on 50*C all day.
richban
19th December 2015, 13:27
HI All.
I / We are in the market for some single ring pistons for our NSR300's. There is nothing out there so we are thinking of designing our own and have them forged for us.
Can anyone recommend a very good manufacture to contact. It would not be a massive order maybe 32 pistons.
I will be emailing Wiseco Wossner etc. But if someone has direct contact that would be of help.
Much Thanks Rich.
husaberg
19th December 2015, 13:35
HI All.
I / We are in the market for some single ring pistons for our NSR300's. There is nothing out there so we are thinking of designing our own and have them forged for us.
Can anyone recommend a very good manufacture to contact. It would not be a massive order maybe 32 pistons.
I will be emailing Wiseco Wossner etc. But if someone has direct contact that would be of help.
Much Thanks Rich.
You Don't need to go forged.............modern cast is more than man enough.
(Unless its turbo or supercharged or burning exotic fuels)
Vertex as well
seen these
https://id3528.securedata.net/test.burrisracing.com/merchantmanager/product_info.php?cPath=70_122&products_id=483
whoops 14mm pins
richban
19th December 2015, 13:51
You Don't need to go forged.............modern cast is more than man enough.
(Unless its turbo or supercharged or burning exotic fuels)
Vertex as well
We will see. I think if we ran cast pistons with the heat issues we have had they would last 5 mins. The forged ones take a beating. To be honest I don't know much about the subject to comment. I will ask the people that make them.
richban
19th December 2015, 13:53
seen these
https://id3528.securedata.net/test.burrisracing.com/merchantmanager/product_info.php?cPath=70_122&products_id=483
whoops 14mm pins
And compression hight way way out. We run KR150 Wiseco pistons at the mo.
husaberg
19th December 2015, 14:08
And compression hight way way out. We run KR150 Wiseco pistons at the mo.
tis was a ultra quick google
We will see. I think if we ran cast pistons with the heat issues we have had they would last 5 mins. The forged ones take a beating. To be honest I don't know much about the subject to comment. I will ask the people that make them.
Forged has better mocecular structure but cast pistions can use better materials now.
Like everything there is a trade off/compromise.
Pretty sure both the RSA and Honda RS pistons were all cast rather than forged
http://www.pit-lane.biz/t3173p340-gp125-all-that-you-wanted-to-know-on-aprilia-rsa-125-and-more-by-mr-jan-thiel-and-mr-frits-overmars-part-2-locked
http://www.pit-lane.biz/t3173p320-gp125-all-that-you-wanted-to-know-on-aprilia-rsa-125-and-more-by-mr-jan-thiel-and-mr-frits-overmars-part-2-locked
http://www.pit-lane.biz/t4072p220-gp125-all-that-you-wanted-to-know-on-aprilia-rsa-125-and-more-by-mr-jan-thiel-and-mr-frits-overmars-part-3-locked
Wobbly redesigned the shape on the BSL pistions of about that bore size pretty sure it was Woosner that supplied the pistions, Wob might share?
Barikit might be worth a try as well
i note they seem to do a NSR sized competition big end bearing.
25mmx32mmx16mm. ( i haven't check my data but that seems about the right size)
Also i never knew the MC16 crank accepted RS125 rods on account of its 24mm pins.
Turns out the later ones MC18 on generally have to use Samarin rods or CRM125 Honda (ie NSR125)
http://www.kiwibiker.co.nz/forums/showthread.php/155339-NSR250-rebuild-The-ELF-Special?p=1130454811#post1130454811
wobbly
19th December 2015, 16:39
The same point about material advances applies to forgings - they are now run at the same clearances as top notch Jap cast pistons..
The only way to go in my opinion is Wossner - to many horror stories from Wiseco.
I can get direct into the CAD side of Wossner and organise any piston you want.
And have been using a 60mm design for ages in various engines and have a few ready to go into the NSR300s I am building.
This is based on Wossners HRC RS125 design, but if you stick with that you will have to bore the cylinders for the oversize and replate ( but thats also a good time to port them properly ).
It has a single ring pinned on centre so you can grind on the B ports and has gas ports in the ring groove.
The deck height is 29.5 and with 113 rods from Samarin no deck machining is needed ( good as the case is too small anyway ).
Im about to order some more - and could ask if they could adapt the design in 59.5 size ( dont know if the have that ring ).
richban
19th December 2015, 18:15
The same point about material advances applies to forgings - they are now run at the same clearances as top notch Jap cast pistons..
The only way to go in my opinion is Wossner - to many horror stories from Wiseco.
I can get direct into the CAD side of Wossner and organise any piston you want.
And have been using a 60mm design for ages in various engines and have a few ready to go into the NSR300s I am building.
This is based on Wossners HRC RS125 design, but if you stick with that you will have to bore the cylinders for the oversize and replate ( but thats also a good time to port them properly ).
It has a single ring pinned on centre so you can grind on the B ports and has gas ports in the ring groove.
The deck height is 29.5 and with 113 rods from Samarin no deck machining is needed ( good as the case is too small anyway ).
Im about to order some more - and could ask if they could adapt the design in 59.5 size ( dont know if the have that ring ).
I will have to talk to the Boys. We were thinking of going the whole hog with the longer rods rebore and plate. So 60mm is sweet. Just have to cost it all up. If you have a cost for the rods and pistons please let me know.
Ta Rich.
Flettner
19th December 2015, 18:38
Here is another small item in the TZ400 - a double sized CNC waterpump impeller,it sits on 50*C all day.
Is that one of the ones we made?
seattle smitty
19th December 2015, 19:02
I'm late to the Lectron discussion by a couple of pages, but Wayne, maybe you will opine about this one, seeing as you work on karts that flat-turn, as well as bikes that lean. Alcohol-burning outboard hydros flat-turn, of course, and always do so to the left (if we tried to set up a tight course that turned both ways it would surely result in much bloodshed; when you go into a turn with eleven other boats and you aren't up front, visibility is poor or worse, but if all turns are to the left you can sort of feel your way around with occasional glimpses). In the last 20-25 years, powerheads (flat-twins and flat-fours) are commonly mounted with the cylinders pointing left and right, the pipes pointing aft, the carb throats toward the front of the boat. Given the centrifugal forces in the corners, the carbs are frequently mounted at an angle, with the tops canted up to maybe 30 degrees to the left, float-bowls to the right, so that the fuel doesn't slosh excessively to one side of the bowl.
So you know all that anyway, Wayne; my question is whether Lectrons are more/less affected by these forces than Mikunis, and would you cant them over to one side in this manner, were you building an outboard?
husaberg
19th December 2015, 19:09
I'm late to the Lectron discussion by a couple of pages, but Wayne, maybe you will opine about this one, seeing as you work on karts that flat-turn, as well as bikes that lean. Alcohol-burning outboard hydros flat-turn, of course, and always do so to the left (if we tried to set up a tight course that turned both ways it would surely result in much bloodshed; when you go into a turn with eleven other boats and you aren't up front, visibility is poor or worse, but if all turns are to the left you can sort of feel your way around with occasional glimpses). In the last 20-25 years, powerheads (flat-twins and flat-fours) are commonly mounted with the cylinders pointing left and right, the pipes pointing aft, the carb throats toward the front of the boat. Given the centrifugal forces in the corners, the carbs are frequently mounted at an angle, with the tops canted up to maybe 30 degrees to the left, float-bowls to the right, so that the fuel doesn't slosh excessively to one side of the bowl.
So you know all that anyway, Wayne; my question is whether Lectrons are more/less affected by these forces than Mikunis, and would you cant them over to one side in this manner, were you building an outboard?
I am not Wayne obviously but interestingly the one or two Edmondson predecessors to the Lectron had no float chambers
Lake injector was one and i can't remember the other name (if it did exist) (later it was called the POS-A-Fuel)
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=302528&d=1411868143
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=302531&d=1411868143
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=302530&d=1411868143
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=302529&d=1411868143
Neil made one that he had on the Kawasaki big horn prior to the EFI.
this is the story up to the Quick silver (Later Edlebrook)
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=301700&d=1411459175
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=301699&d=1411459175
wobbly
20th December 2015, 09:01
With my experience of kart carb setup, the only way to go is "pump around ".
This eliminates the fuel height changes in the bowl due to float bounce or any issues from centripetal acceleration forces.
If you dont know about this,its simple.
The carb float is removed and fuel is pumped ( from the usual round Mikuni pulse pump ) into the carb via the open needle valve hole.
Another fitting or tube is added at the correct fuel height, and this is plumbed to the suction side of another pulse pump ).
This sends the excess fuel back to the tank.
In your case where the fuel always sloshes to one side, then that would be the side to draw from.
The bowls are filled with tank foam to reduce the fuel swirling about at the main jet height.
Works perfectly.
Here is a shot of the system on a KTM 250 for road racing.
The two pumps are secured to a plate back to back with the pulse line fitted into that with a cross hole to operate both diaphrams.
And in the case shown the suction side is the original fuel entry, as it just happened to be the right level.
Re the Lectrons, one style of bowl has individual floats that slide on rods, so any variation in fuel height side to side is taken care of by this system.
But even then I would dump the floats and use pumparound.
Edit - yes the waterpump impeller was hoovered up by our resident CNC man, Flettner from Autoflight.
Flettner
20th December 2015, 12:06
With my experience of kart carb setup, the only way to go is "pump around ".
This eliminates the fuel height changes in the bowl due to float bounce or any issues from centripetal acceleration forces.
If you dont know about this,its simple.
The carb float is removed and fuel is pumped ( from the usual round Mikuni pulse pump ) into the carb via the open needle valve hole.
Another fitting or tube is added at the correct fuel height, and this is plumbed to the suction side of another pulse pump ).
This sends the excess fuel back to the tank.
In your case where the fuel always sloshes to one side, then that would be the side to draw from.
The bowls are filled with tank foam to reduce the fuel swirling about at the main jet height.
Works perfectly.
Here is a shot of the system on a KTM 250 for road racing.
The two pumps are secured to a plate back to back with the pulse line fitted into that with a cross hole to operate both diaphrams.
And in the case shown the suction side is the original fuel entry, as it just happened to be the right level.
Re the Lectrons, one style of bowl has individual floats that slide on rods, so any variation in fuel height side to side is taken care of by this system.
But even then I would dump the floats and use pumparound.
Edit - yes the waterpump impeller was hoovered up by our resident CNC man, Flettner from Autoflight.
Ha Ha, nothing new aye, I had an old stationary engine (turn of last centery) that pumped fuel up to a bowl with a divider (dam) with a small "v" cut into it. This was the fuel height as the extra fuel went over the V and back to the tank. And I'll bet someone thought of it before that too :lol:
Grumph
20th December 2015, 13:26
Ha Ha, nothing new aye, I had an old stationary engine (turn of last centery) that pumped fuel up to a bowl with a divider (dam) with a small "v" cut into it. This was the fuel height as the extra fuel went over the V and back to the tank. And I'll bet someone thought of it before that too :lol:
Technically, it's a weir arrangement. Yes, very old, particularly in rivers...Rex McCandless played around with weir type "float bowls" on works Nortons in the 50's. He had a hatred of floats or as he called them, cisterns. Quoted as saying his toilet wouldn't stop flooding so why use the same setup on a bike....
seattle smitty
20th December 2015, 15:36
I never had heard of putting a suction pump on the fuel-out side, but in the days when a lot of guys were converting the Carter N carbs from old Mercurys to alcohol, floatless arrangements were very common. I even built a set of three floatless carbs from billet on my little Sears Craftsman lathe. 2'" 6061 bar stock, one piece for the throttle body, the other for the bowl and end caps, and a funnel of Delrin for the overflow. Beautiful, if functionally crude.
H-berg, I remember seeing ads for the Lakes injector. At one point I believe the rights to it were bought by somebody in the light aircraft industry, even got FAA approval. The office was supposed to at Renton (Washington State) Airport where I was learning to fly; I looked for it one day, but don't recall now whether I found it or talked to anybody. The aircraft version might have been larger than the original Lakes Injector, which I recall being made primariy for karters, with a bore of around 25mm. I'll look at your inks again, fun old stuff.
I suppose there must be a "tank foam" that stands up to methanol and the other fractions.
Do any of the kart classes run alcohol these days, as they did long ago? The only motorcycles I remember running alcohol, besides the drag bikes, were the "speedway" dirt track bikes, an interesting in-crowd sport mostly in southern California, IIRC. Oops, just did a quick google, and I see there is speedway racing Down Under. Serious racing, but looks sort of like drift-cars but with bikes.
Well, also it might be that the pari-mutuel gambling motorcycle racers in Japan run alcohol. I never saw them when I was living in Japan in 1970, but I did spend an afternoon at the gambling boat races. Twenty four marine stadiums built for the purpose, tons of money involved. I've often thought if amateur outboard racers in the US could work out arrangements to where people could gamble on our races, there would finally be money in the sport, and a guy could make a living at the thing he loved.
http://www.aeroconversions.com/products/aerocarb/index.html
http://www.ellison-fluid-systems.com/
wobbly
20th December 2015, 15:56
No kart classes allow Alky to my knowledge, and the only bike classes are Pre 72 Post Classic air cooled.
Yes speedway solo's use it in the Jawa engines, but thats about it nowdays.
The tank foam I bought off Ebay is Alky resistant from memory.
karter444
20th December 2015, 18:51
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The Dam Question!
Chambers has fitted an exhaust port dam to his RG50 cylinder. It was hand shaped out of alloy and is held in place with a screw and sealed with Balzona epoxy.
We hope to get to test it on the dyno in the next night or two.
The top of the exhaust port is 85% wide and the dam fills the lower part of the original exhaust port and tapers out to the pipe diameter at the end of the exhaust duct.
maybe due to the size and angles of the port there was no short circuiting and therefore nothing to be gained by doing the raised port floor , but maybe now that the dam has been put in the A transfers could be widened and reangled for more power .But this still [apart from heat transfer issue ] doesn't explain the loss in power with the dam fitted , maybe Wobbly could explain whats happening in the exhaust duct with regards to pressure and gas velocity in relation to piston position .With my limited knowledge it seems that the lower part of the ex port is only providing a large radius to gently push the ring back in , but obviously this isn't the case or there would have been no power decrease .Thanks to these guys for sharing this info , I have just welded in a 6 mm wide curved dam into one of our barrels and was going to weld from the dam out to raise the port floor ,but will wait to see the outcome from your dyno tests as I don't have access to a dyno .
looking forward to seeing the final outcome as there has been quite a lot of discussion on this modification
cheers
Haufen
20th December 2015, 23:54
Blue is where we started at the very beginning and after a lot of hard work and careful step wise development we have worked our way to the Red line. ....... :facepalm:
I am sorry for you that it did not work out as planned, and I know that feeling pretty well, too :D Did you reproduce the result with another exhaust pipe, 'just to make sure'?
What I do in a situation like this, is to analyse what else had been affected by the change and then try to learn from it. In your case, time areas and area ratios of the exhaust port come to mind. As well as the distance between the transfer windows and the exhaust port. That seemed to have been on the large side at the beginning already? So maybe you found yourself a kind of "safe distance" for that cylinder and setup which opens the door for further modifications.
By the way, is that a cast iron liner? Looks like the ring is telling you where it wants you to remove some more material and make a nice blending radius at the top of that port. Would be interesting to test that after testing the bottom radius at the dam.
2005bully
21st December 2015, 03:24
[QUOTE=seattle smitty;1130930972]
H-berg, I remember seeing ads for the Lakes injector. At one point I believe the rights to it were bought by somebody in the light aircraft industry, even got FAA approval. The office was supposed to at Renton (Washington State) Airport where I was learning to fly; I looked for it one day, but don't recall now whether I found it or talked to anybody. The aircraft version might have been larger than the original Lakes Injector, which I recall being made primariy for karters, with a bore of around 25mm. I'll look at your inks again, fun old stuff.
I suppose there must be a "tank foam" that stands up to methanol and the other fractions.
Do any of the kart classes run alcohol these days, as they did long ago? The only motorcycles I remember running alcohol, besides the drag bikes, were the "speedway" dirt track bikes, an interesting in-crowd sport mostly in southern California, IIRC. Oops, just did a quick google, and I see there is speedway racing Down Under. Serious racing, but looks sort of like drift-cars but with bikes.
In response to Seattle Smitty......... I was first put on to the LAKE INJECTORS in the 70's by the late E.C. Birt. A with most low production parts in those days it was hard to track down any kind of supply. In the early 80's I found a company by the name of HAPI engines located in Elroy Arizona, that had resurrected a version of the LAKE injector and re-named it "POSA FUEL". The company specialized in adapting VW air cooled engines to experimental aircraft use. The POSA carb was one of the items they marketed for the conversion. I purchased some of the units from them and adapted them to methanol fueled kart engines. Used a pulse pump with a return line that that had an adjustable restrictor. (much like a dial a jet) The POSA did feature a flat sided needle much like the Lectron carbs of today. When tuned correctly the POSA units worked very well. But 50 degrees of cyl head temp or if the sun went behind the clouds, and the tuning process had to be completely re-configured. From later experience with custom made mechanical fuel injectors, I'm sure the results would of been much better with a mechanical pump. HAPI engines went out of business in the mid 80's. I still had one of the POSA units hidden away. Attached a few pictures of it for your review. Also have a couple of the original instruction sheets if your interested...
Methonal resistant "tank foam" is used in most late model and sprint car fuel cells that are run on dirt track ovals.
There are a few 2 stroke race kart classes left in the USA that allow "open" fuel...... Methanol / Castor oil is the preferred choice of most.... Here at the shop we build a fair number of methanol carbs for the 2 stroke kart market. But it seems most 2 stroke products today, are in the same position as the last guy making buggy whips, If you stay in the game you keep getting a larger percentage of an ever smaller market. Kermit Buller
Frits Overmars
21st December 2015, 04:15
That POSA carb seems to be next of kin to a Gardner:
318077 318078
seattle smitty
21st December 2015, 04:36
Sprint cars, of course, should have thought of them having foamed tanks. Thanks Kermit. I remember seeing the name E.C. Birt . . .
How long have you been around karts? Was talking to some bikers about the slider-pipes that outboard racers use; those are impractical for bikes, but some of the sprint kart guys in the late-'60s/early-'70s had movable baffle-cones. They set the length in the pits, then track-tested and made further adjustments as appropriate. This is a trick that could easily be applied to a bike by any of the 2-stroke bucket racers or even street riders here, giving additional tune-ability (could be a good thing, though it violates the KISS principle).
Do you recall these adjustable baffle cones?
(EDIT) Found info on E.C. Birt, interesting man, if anyone's curious: http://articles.superhunky.com/bio/E.C.%20Birt
husaberg
21st December 2015, 06:08
That POSA carb seems to be next of kin to a Gardner:
318077 318078
very much so.
A nephew even of the Wal Philips
H-berg, I remember seeing ads for the Lakes injector. At one point I believe the rights to it were bought by somebody in the light aircraft industry, even got FAA approval. The office was supposed to at Renton (Washington State) Airport where I was learning to fly; I looked for it one day, but don't recall now whether I found it or talked to anybody. The aircraft version might have been larger than the original Lakes Injector, which I recall being made primariy for karters, with a bore of around 25mm. I'll look at your inks again, fun old stuff.
Kermit Buller
Yes it was red I have some links to them I have posted.
2005bully
21st December 2015, 06:08
Sprint cars, of course, should have thought of them having foamed tanks. Thanks Kermit. I remember seeing the name E.C. Birt . . .
How long have you been around karts? Was talking to some bikers about the slider-pipes that outboard racers use; those are impractical for bikes, but some of the sprint kart guys in the late-'60s/early-'70s had movable baffle-cones. They set the length in the pits, then track-tested and made further adjustments as appropriate. This is a trick that could easily be applied to a bike by any of the 2-stroke bucket racers or even street riders here, giving additional tune-ability (could be a good thing, though it violates the KISS principle).
Do you recall these adjustable baffle cones?
(EDIT) Found info on E.C. Birt, interesting man, if anyone's curious: http://articles.superhunky.com/bio/E.C.%20Birt
Buller built was incorporated in 1978. Starting in the early 70's I did all sorts of 2 stroke work, became pretty well karts only by the 80's. Over the years I spent around a decade as an IKF board member, National tech director, Chairperson for the NAKTC, (in charge of North Americas 2 stroke Homologation.) Yes as far as adjustable pipes.... I am very familiar with them. Virtually all of the USA fixed gear pipes have adjustable head pipe lengths. Originally a piece of "flexable" exhaust tubing was used to connect the pipe and header. By changing the length of this "flex pipe" the head pipe length can be adjusted in the pits. Today std ex tubing is used as a connector, but is still referred to as "flex pipe" in karting jargon. On the fly adjustable "slippy pipes" were originally built by the Hartman's in Calif. Later Hartmans expansion chamber business was sold to Rod and Art Verlinger. They still operate as RLV in Santa Maria Calif. To this day Slippy pipes are still legal for the fixed gear lay down enduro karts, and RLV still produces a few of them as they are ordered. The slippy pipes are built with a parallel center section (most usa fixed gear kart pipes are cone to cone) The stinger on this outer baffle cone is very short with an oversized ID. A second baffle cone is positioned inside the outer baffle cone. This second inner baffle cone has a stinger of the proper id and length while its od is a slip fit into the outer cones stinger. At the end of the inner stinger a thick flat washer is welded onto the stinger. This washer has a square notch cut into it that slides along a piece of key stock supported by the silencing can. (this prevents the inner cone from rotating) This washer also has a small hole drilled into it, through which a cable is anchored. The cable is run out through a small tube welded to the silencing can, Eventually the routing of the cable terminates at a steering wheel mounted handle. The pipe can be "pulled" by the driver at any time. Learning to effectively operate one is a great lesson for understanding the relationship of ex temp relative to tuned length. Some of the early karters also experimented with head pipe lengths that were adjustable on the fly, but that was quickly made illegal. Point of interest, The stinger inside the stinger reduces the amount of force pushing the inner baffle back and allows it to be pulled by hand. I don't have any pictures of the internal parts of a slippy but did attached a picture of one from the outside.
I came to know E.C. very well. Often times he was misunderstood by the public for his habit of not following conventional wisdom, which I found very enlightening. RIP E.C.
Kermit Buller
2005bully
21st December 2015, 06:12
That POSA carb seems to be next of kin to a Gardner:
318077 318078
Fritz... That's a new one on me, Never have seen one by that name. From the pictures they look to be a fundamentally identical.
Kermit Buller
Frits Overmars
21st December 2015, 06:49
Fritz... That's a new one on me, Never have seen one by that name. From the pictures they look to be a fundamentally identical.Funny that; I'd never heard of the POSA.
Yes, their principles seem to be identical: a slide that makes for a perfectly smooth inlet tract at WOT, a needle jet that moves with the slide, and a needle that is fixed in the outer carb body, although adjustable because it's threaded. And if you take a look at that second picture: an adjustable main jet where the fuel line attaches to the needle jet. This was not a Gardner original but a private modification. I have a vague notion that Wobbly had something to do with that...
wobbly
21st December 2015, 07:25
I think there are several interlinked effects of lifting the floor ( and or adding larger bottom corner rads ) to an exhaust port.
First off going all the way up to the transfer height, must be considered an " extreme " case, where any one of the effects that is detrimental to power
could easily swamp any smaller effect that would usually be helpful.
If the A port has already a large wall or septum dividing it off from the main port - then I can see that any advantage from the lifted floor via a reduction in short circuiting would be minimal.
Creating a high dam at the port, by inference then means we get back to having a very tapered "diffuser" like duct, with a much bigger exit area than that at the entry point.
And as is well documented, the exact reverse makes better power.
In this case the sim is not very helpful in determining what is optimum, as it takes no account of the change in short circuiting efficiency, only the flow effects on the Mach numbers of the area changes.
Then lastly we have the thermal issue of the insert overheating, due to lack of an efficient heat path to the cooler water or finned cylinder.
Very much a can of worms, not easy to sort the positive effects and be able to identify any general pointers to guide other tuners.
seattle smitty
21st December 2015, 07:32
I think Husaberg's mention of the Wal Phillips injector brings up maybe the earliest of this sort of device in the mid-'60s. I emphasize "maybe." I do believe the Wal-Phillips preceeded the Lakes, Posa, et al, . . . for whatever that's worth . . .
Nice description of "slippy pipes." One of the (so far . . . ) salutary simplicities of outboard racing is that we don't have mufflers to deal with.
Grumph
21st December 2015, 08:21
I think Husaberg's mention of the Wal Phillips injector brings up maybe the earliest of this sort of device in the mid-'60s. I emphasize "maybe." I do believe the Wal-Phillips preceeded the Lakes, Posa, et al, . . . for whatever that's worth . . .
The Wal Phillips which was a very simple gravity feed, butterfly throttle device preceded the Gardner which was a very effective and complete carburettor.
Gardner was written up in the UK mags several times in the late 50's and early 60's. His carbs went through several variations until they were as is still available now. What he was doing was widely publicised in the motorcycle press, certainly the English language ones, possibly Continental ones too.
Wal Phillips was an ex speedway rider and initially saw his injector as a simply set up replacement for a carb on alky burning speedway singles. If you go back even further, it has many similarities to the Binks "mousetrap" carb of the 20's which was ideal for speedway as it was either on or off....and nothing in between.
husaberg
21st December 2015, 16:24
Fritz... That's a new one on me, Never have seen one by that name. From the pictures they look to be a fundamentally identical.
Kermit Buller
Funny that; I'd never heard of the POSA.
Yes, their principles seem to be identical: a slide that makes for a perfectly smooth inlet tract at WOT, a needle jet that moves with the slide, and a needle that is fixed in the outer carb body, although adjustable because it's threaded. And if you take a look at that second picture: an adjustable main jet where the fuel line attaches to the needle jet. This was not a Gardner original but a private modification. I have a vague notion that Wobbly had something to do with that...
The Wal Phillips which was a very simple gravity feed, butterfly throttle device preceded the Gardner which was a very effective and complete carburettor.
Gardner was written up in the UK mags several times in the late 50's and early 60's. His carbs went through several variations until they were as is still available now. What he was doing was widely publicised in the motorcycle press, certainly the English language ones, possibly Continental ones too.
Wal Phillips was an ex speedway rider and initially saw his injector as a simply set up replacement for a carb on alky burning speedway singles. If you go back even further, it has many similarities to the Binks "mousetrap" carb of the 20's which was ideal for speedway as it was either on or off....and nothing in between.
318089
I have posted some stuff on all of them including the mouse trap.
I will dig it up latter.
Gardner made a set of carbs for the Dual valve Exactaweld (whoops it was the Armstrong)
A few used to gun them on the early clasics including from memory Bill Swallow of the 3 bearing Velo modified Norton into a near Seeley thing he used to race.
https://c1.staticflickr.com/3/2810/10042872034_880e6ccb21_b.jpg
I am not sure if the Gardner had a conventional needle or funny shape like the posa, lake,EI, Bluestreak, lectron, Quiksilver Edlebrock, Smart family
257204257205257206
Working on the EI carb with the 24mm venturi behind the slide, its a bit of a trick getting the mixture right. Its easy to wind the needle up and down and have it either rich on top lean below or the other way around. But not having a good selection of needles, I am having to stone the flats on the two needles I have, to try and get a profile that fuels correctly.
257208257203257207
A comparison of the OKO with the 24mm restriction in the bellmouth like Frits suggested (Red Line) and the EI carb with the venturi behind the slide idea (Blue Line).
I am still working on tuning the EI carb and haven't completly given up on the venturi behind the slide idea yet but the 24mm venturi restriction in the bellmouth concept does look promising.
That is exactly the issue everyone has had with Lectron and EI carbs.
Get the mid spot on and the top will be rich, jet the top correct and the mid will be lean - no matter what needle is used.
I have said for years that a solenoid powerjet ( or adding a proper air correction system) would fix everything, but that needs alot of work to set up, so has never been done.
Its worth doing though, as the nice atomisation of the Lectron setup is worth having.
Another route would be a powerjet with air correction, these are available - I will post a link here when I find it.
Another possibility is the company that bought the patents from Edmonson - the guy who did Lectron and EI.
These new carbs won everything at Pikes Peak where they ran.
The 2T Quad had my pipes and was easily the fastest on the hill - listen for the screaming Banshee.
http://www.youtube.com/watch?v=ZneHutHgUi4&lr=1&user=motovox
Here is the air corrected powerjet setup - I have a pair and will test these on the first F3 - 400 engine on the dyno
http://www.thunderproducts.com/dial_a_jet.htm
Here is some more stuff i sent TZ a while Back
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257214257220
heres the other offshoot of the lectron lake etc
http://revmasterautomotive.com/revmasteraviation/?p=221
seen these talked about never a look though.
257215
http://www.aeroconversions.com/produ...arb/index.html (http://www.aeroconversions.com/products/aerocarb/index.html)
257216
Plus another
257222
http://www.psicarbs.com/bigair.php
http://www.saltmine.org.uk/dale/dale-faq.htm
Eplanation here "
The Lectrons have a central fuel outlet, that being the needle area. The needles controlled all fuel now with the exception of the power jet. One of the ideas was to eliminate the rich and lean spots in the fuel delivery curve as can happen with a multi-area delivery device such as a normal carb. The other was to make a system that was easy to adjust. Lectron succeeded brilliantly in one area, failed miserably in the other.
Fuel control was with the needle. A taper was ground into the needle on the side that faces the intake area of the engine. Needles were graded and marked 5-3, 6-1, 6-2 etc. These numbers were easy to understand. The first number was the overall richness of the needle. A 5 series was leaner than a 6 series. The second number was the midrange richness. A -3 was richer than a -1. The very top end was controlled by the power jet exactly as we understand power jet function now.
In order to have a "base" point that tuning could be initially set to, a distance was specified as standard, a datum. This was the length of the needle from the adjusting nut(what would be the needle clip in a Mikuni) and the tip of the needle that extends into what would be the needle jet in a Mik. The "needle jet" was not adjustable, much like the TMX style of Mik. The standard length was 1.945" or something like that. If the length was longer, the overall fuel was leaner as the taper would be lower and this would allow less fuel for any given throttle opening. The opposite was true if the needle length were shorter than 1.945". I think that if you had to go more than 2 turns in either direction, it was time to change the needle for a different fuel curve. This allowed for the fine adjustment of fuel.
If one were to replace the screws holding the top of the Lectron with snap clips to allow quick removal of the top, a minor needle adjustment with power jet swap could be made in about 2 minutes for 2 carbs. This was one of the Lectrons strong points.
If jetting was ok in the mid-range but off a bit just before power jet came on, you wouldn't want to adjust the needle as this would upset the balance with the mid-range. You would select a needle with a different second number - 1, -3 etc. THIS is where the Lectron failed. The quality control of the grinding of the needles was such that even though you had two needles marked the same, it didn't mean that you hade two needles that were the same. At first this caused all kinds of confusion as one would change the needles expecting a change in a known area and the engine wouldn't run anything like what was expected. Only after measuring the needles very accurately at absurdly small stations were we able to ferret out that Lectron needles were ground by the firm of "Byguess and Bygolly"!
The only way to solve this problem was to carefully hone stone the needles and hope that the results gave you a pair of needles that could be used together, run them, grade them, and hope that one was fortunate enough to get a selection after a while. With all this tuning work done to the needles, it's not hard to see that if one had a good set, they didn't get loaned out at all(Hey! I need as set of 6-2's. Got any I could borrow for this race?) Might as well part with your right arm once your friend figures out your needles work better than his!
On of the other strong points was that without a pilot circuit, the Lectrons could be run at absurd angles(35 deg) compaired to the Mik's. This allowed the carbs to be mounted to a straight manifold on the Super-street RD's for a more direct shot at the intake. If a Mikuni was mounted this way, it would flood horribly under hard braking as fuel poured out of the pilot circuit. This was not a problem with the central fuel point on the Lectron's.
But time moves on and the quality control finally caught up to Lectron(and some other problem with finances or something). Carb technology advanced as well and we have very good, though expensive stuff now that needs computers to do all the thinking where us mortal humans did it before. This is progress...I think."
http://www.ozlaverda.com/what-s-an-e...or-t15-10.html (http://www.ozlaverda.com/what-s-an-ei-caburetor-t15-10.html)
257217
I knew i had seen this somewhere explanation of the "cheater" Carb for controlled carb classes
http://lectronfuelsystems.com/faqs.html#Tuning
What is a Lectron High Velocity Carburetor?
The standard Lectron carburetor has a 2mm taper. For example a 40mm carburetor will start out 40mm and taper down to 38mm at the fuel pick up then taper back up to 40mm. The Lectron High Velocity carburetor has a 4mm taper. For example, a 38mm HV carburetor will start at 40mm and taper down to 36mm at the fuel pickup then back out to a 38mm. This carburetor was first designed for racing classes that had a restriction on carburetors size. This was Lectron’s answer to have a small carburetor work like a big carburetor. The Lectron High Velocity carburetor is also used today for bikes that do not have much “port speed”. Engines with a small amount of port speed have trouble picking up fuel efficiently this carburetor corrects that. Final note, many people put Lectron High Velocity carburetors on engines not understanding why? Just because of the name “High Velocity” they think it is a better carburetor than the standard Lectron.
Don’t confuse the issue.
History of Reds Carbs from what i understand Red or his son was in business with one of Kenny Roberts sons. Wob would know for sure, but i think his son may have worked for KR.
History Behind the AFT Carburetor
Since the beginning of the combustion engine, man has had a natural desire to get as much power out of the wide variety of motors manufactured for work and play. For the past 37 years, William “Red” Edmonston has chosen the motorcycle as his passion for power and speed.
Red started racing Triumph motorcycles in the 1940’s and after 13 years of racing and breaking bones, he decided to move to California and work with Triumph as a road manager as well as open a Honda dealership to provide for his young family. During the 1960’s, Red continually became frustrated with the fuel delivery systems for the motorcycle industry. Most of the carburetors being manufactured and sold on motorcycles were complex to tune, and required a constant effort to keep tuned for proper operation of the motor. This was primarily because of the multiple and overlapping circuits (different jets for the differing throttle positions) that caused the air fuel mixture to be very rich at different throttle positions. These early carburetors could not adapt for altitude changes either, which added to the constantly differing air-to-fuel ratios and tuning problems. Besides the frustrations that many had with keeping their motorcycles running at optimum, these crude fuel delivery systems also cause the motor to run very inefficiently and with significant harmful emissions.
In the late 196o’s, after many years of racing, managing race teams, and selling motorcycles, Red began his long career of inventing, designing, and manufacturing carburetors for the motorcycle industry. In short, Red has had a significant impact on the motorcycle industry over the past 40 years. Red has held nearly 100 patents and has invented and manufactured nine different carburetors, each of which has shared some similarities while each subsequent model continually added improvements in functionality and performance. The history of the Red Edmonston’ carburetors spans many years and a great deal of experience and improvements:
· 1968-1969: The Lake Injector prototype and final production model carburetor.
· 1970-1971: The Pos-A-Fuel prototype and final production model carburetor.
· 1971: The Pos-A-Fuel with remote float bowl production model carburetor.
· 1973-1974: The Lectron prototype and final production model carburetor.
· 1976-1977: The E.I. Prototype and final production model carburetor.
· 1978: The Blue Magnum production model carburetor.
· 1980: The Bank of Four Blue Magnum model carburetor.
· 1981-1982: The Qwik Silver prototype and production model carburetor.
· 1982: The Qwik Silver Bank of Four carburetor wins Daytona super-bike race.
· 1993: The Qwik Silver II production model carburetor (sold to Edelbrock).
Lastly i think Mike Sinclair was meant to be a gun out sorting out Lectrons i read somewhere. I guess possibly through the Roberts days connection exposure.
.
Any guesses where the manufacturer measures the size of this...........
226862 Venturi Flow Tube
I think that if I use a 24mm design like this, but with a main jet setup like a Gardner carburettor instead of an injector I could push the GP to over 30hp.
226863 Gardner Carb
When I think about it a 38mm carb could be modified with one of these so the narrowest part of the 24mm venturi is where the manufacturer originally sized their old carb.
So all legal by the definitions I have seen posted lately.
That to be legal a modified carb has to be measured at the same place the manufacturer originaly did.
FXR's are great and they are the bike to beat at Mt Welly and they have brought many new people into the sport and thats very good but if you want something special you still have to make it yourself, and I imagin thats what the old style spirt of Buckets was about.
Some interesting 50cc stuff here:- http://www.elsberg-tuning.dk/monark.html
The only good pic I could find of Gardner.
With the long bellmouth version I can see why a TZ350 would work well,the correct tuned length for peak at 10,000 is near double that of a stock 38mm Mikuni.
http://kioteegarage.blogspot.com/2011/10/flat-slide-history.html
I thought i had posted a pic of them but only a brief description TZ has posted a picture of one with a mattchbox float
But here is one with a bolt on Stack.
Bill Swallow or his brother used to use one on a real fast ohv velo.
Also when the classic movement started again i believe he started to manufacture them.
http://www.flickr.com/photos/slrosko/4636268333/
That is exactly the issue everyone has had with Lectron and EI carbs.
Get the mid spot on and the top will be rich, jet the top correct and the mid will be lean - no matter what needle is used.
I have said for years that a solenoid powerjet ( or adding a proper air correction system) would fix everything, but that needs alot of work to set up, so has never been done.
Its worth doing though, as the nice atomisation of the Lectron setup is worth having.
Another route would be a powerjet with air correction, these are available - I will post a link here when I find it.
Another possibility is the company that bought the patents from Edmonson - the guy who did Lectron and EI.
These new carbs won everything at Pikes Peak where they ran.
The 2T Quad had my pipes and was easily the fastest on the hill - listen for the screaming Banshee.
http://www.youtube.com/watch?v=ZneHutHgUi4&lr=1&user=motovox
Here is the air corrected powerjet setup - I have a pair and will test these on the first F3 - 400 engine on the dyno
http://www.thunderproducts.com/dial_a_jet.htm
As interesting as this TZ
http://2stroker.createforumhosting.com/armstrong-motorcyles-t3382.html
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I posted some Posi carb pics a while back and alluded to an article I had read
Here it id the observant amonst you will note how slim it is and how it was designed by the same guy that did the Posi, Lectron, EI and Edlebrock quicksilver and no doubt heaps more.
He later said he was good at imaking HP carbs not so good at choosing business partners. His son worked with Kenny Roberts son Curtis interesting.
This carb came after the Ron Gardner flatside. I have never seen pics of the insides of a Gardner carb. But they had a remote float.I think honda had flatslides in the early 60's
. Like so:
249188
The first bike I can remember with the 2 stage carb set up was the Villiers Starmaker stuff I poster further back.Yamahas had a big play with them in the mid 80's to 90's TT and XT etc. Honda with the XR series in the Mid 80's one thing they all have in common is they all went back to single carb set ups.The (TTR way be an exception to this rule)
2 carbs in my opinion = twice the drama.
I have enough trouble tuning one as it is.
Picture of updraft carbs on MZ and Suzuki 60's bikes a pic of the DKW 250 supercharged Twingle and lastly a Binks mousetrap variable venturi carb I had heard of them but I had never seen a picture of one.
318083318084
53mm at least well I never knew that anyway...by the wording it looks like they may even go bigger to special order.
http://www.lectronfuelsystems.com/carburetor/images/50mmPJ250.jpg
I posted this a while back I was hoping to find out something about them?
Go Karb Fuel Injection Carburetor
I seen this on Ebay.
1-13/16" center to center on mount holes. 3/4" across throat
http://www.ebay.com/itm/Vintage-NOS-Go-Kart-Go-Karb-Fuel-Injection-Carburetor-McCulloch-West-Bend-Rupp-/251908761617
Never seen or heard of them guessing it is a single circuit carb like a Wal Philips injector.
Anyone just out of curiosity know anything about them picking 60's Tech.
312554312555312556312557312558312559
husaberg
21st December 2015, 17:51
other stuff that would not fit
318085318086318087318088
Flettner
21st December 2015, 18:23
Behold, the lake injector, (piece of shit), spent hours soldering and filling that bloody needle then the tuning would change depending on the load of fuel (head of pessure)!! Sooo I fit a fuel pump to keep the head of pressure constant but that meant I had to change the needle again:facepalm:
So screw that, went to EFI, hid it inside so as not to upset the rule makers, and wow, you can stick your Lake Injector where the sun don't shine!!!.
http://i1056.photobucket.com/albums/t380/uniflow/36e7999c.jpg
Nah this is pretty (er)
http://i1056.photobucket.com/albums/t380/uniflow/IMG_0522_zpsce09d679.jpg
And at idle
http://i1056.photobucket.com/albums/t380/uniflow/IMG_0523_zps0178bbce.jpg
I'm not a fan of the LAKE, clearly.
husaberg
21st December 2015, 18:35
Behold, the lake injector, (piece of shit), spent hours soldering and filling that bloody needle then the tuning would change depending on the load of fuel (head of pessure)!! Sooo I fit a fuel pump to keep the head of pressure constant but that nean I had to change the needle again:facepalm:
So screw that, went to EFI, hid it inside so as not to upset the rule makers, and wow, you can stick your Lake Injector where the sun don't shine!!!.
http://i1056.photobucket.com/albums/t380/uniflow/36e7999c.jpg
Its still pretty Neil, You can dress up as Grumph and deliver it here when you are down at Xmas if you want.:msn-wink:
SwePatrick
21st December 2015, 21:20
As a big thanks to all in this thread,, i have learned a lot!
Ofcourse i had some knowledge before.
But it has been raised way higher.
Thanks everybody for not keeping things secret. =)
Merry christmas and a happy New year.
From me to all of you:
my little projektengine(beside the big 132cc)
Setup:
Ported Autisa 45.5mm bore, durations: 202/136/138/138
Modified head. 13-1 compression
Top racing crank 41.4mm stroke
std unmodded piston, but just one ring, there are grooves for two, with two rings i don´t see any gains at all, just a lot of wear.
'Derbi style' reed (0.4mm carbon)
Keihin 27mm roundthrottle, from an -83 cr80, totally unmodded. jetted 42/128 and needle in the middle position
CR85 inletrubber
Pvl '458' ignition
6spd gearbox
Cr85 clutch
Morbidelli pipe from the gp twin.
A view down in cylinder at dynosheet(at the sprocket):
318090318091
adegnes
21st December 2015, 23:11
As a big thanks to all in this thread,, i have learned a lot!
Ofcourse i had some knowledge before.
But it has been raised way higher.
Thanks everybody for not keeping things secret. =)
Merry christmas and a happy New year.
From me to all of you:
my little projektengine(beside the big 132cc)
Setup:
Ported Autisa 45.5mm bore, durations: 202/136/138/138
Modified head. 13-1 compression
Top racing crank 41.4mm stroke
std unmodded piston, but just one ring, there are grooves for two, with two rings i don´t see any gains at all, just a lot of wear.
'Derbi style' reed (0.4mm carbon)
Keihin 27mm roundthrottle, from an -83 cr80, totally unmodded. jetted 42/128 and needle in the middle position
CR85 inletrubber
Pvl '458' ignition
6spd gearbox
Cr85 clutch
Morbidelli pipe from the gp twin.
A view down in cylinder at dynosheet(at the sprocket):
318090318091
Cool, more pics!
Here's an update from Norway:
The Peugeot Spx m50 engine is assembled and ready to be mounted in the frame.
318093
My dyno is up and running. (notice choice of bike)
318094
Made this "arduino shield" to go with it. It has inputs for engine rpm, roller rpm and ambient temp. Next revision will have egt and cht to.
318092
I've experienced problems with noise from the ignition when using the rpm pickup circuit on a breadboard, hopefully thats solved now with this shield incorporating a proper ground plane and more decoupling.
Looking forward to seeing if the 22odd hp engmod is claiming is actually present, though I've probably goofed up something.
Merry Christmas!
SwePatrick
21st December 2015, 23:23
I have a lot of noise from ignition too, but i´m running a small easy pull just on a specified rpm.
In that way i can calculate the engine rpm against the dyno rpm.
In Performancetrends dyno setup one can then fill in an gearrate.
Then software knows egnine´s rpm when cancelled that cable.
If nothing is slipping in transmission you get really nice data.
Rgds
Patrick
wobbly
22nd December 2015, 07:41
SwePat,a free Xmas gift for you, may I suggest you polish that piston in a lathe to a mirror finish.
The dark, crater surface will be absorbing a huge amount of combustion heat ( like having fins all over the surface ) that should be heating the gas
and pushing the piston down - not making it bigger.
This was done at Aprilia, and I have been doing it for years on all race engines.
Re the ignition noise - use a resistor plug and cap, this will remove most of the RF in the ignition lead.
SwePatrick
22nd December 2015, 08:06
Hi wobbly,,, yes i know about the 'mirror effect', but actually, i can´t see any difference to this surface.
That means i have tested already,(but in an another cylinder).
There are also other theories why i left it as is in this one.
I wanted to let it build carbon.
In Dragracing with foulstrokeengines, turbo or nitrous gas there are gains with carbonbuildup.
As it actually makes a insulatebarrier and is more 'adhesive' for the protective 'surface gas'.
That means you can go harder on the ignition and have some protection.
But still,, i might revert to polished again if i see losses.
Nothing is carved in stone.
And for resistor, yes!
But i have sometimes misfireproblems that nonresistor cable,cap and plug sorts out.
Rgds.
wobbly
22nd December 2015, 12:09
If the ignition miss fires with resistors then it hasnt sufficient power - drop the spark gap to less than 0.5mm
TZ350
22nd December 2015, 17:07
My dyno is up and running. (notice choice of bike)
318094
Suzuki GP ...... :2thumbsup
TZ350
22nd December 2015, 17:44
317983 317984
The Dam Question!
Chambers has fitted an exhaust port dam to his RG50 cylinder. It was hand shaped out of alloy and is held in place with a screw and sealed with Balzona epoxy.
The top of the exhaust port is 85% wide and the dam fills the lower part of the original exhaust port and tapers out to the pipe diameter at the end of the exhaust duct.
317998
Red line is with the exhaust port dam, no other changes.
317999
Blue is where we started at the very beginning and after a lot of hard work and careful step wise development we have worked our way to the Red line. ....... :facepalm:
I think there are several interlinked effects of lifting the floor ( and or adding larger bottom corner rads ) to an exhaust port.
First off going all the way up to the transfer height, must be considered an " extreme " case, where any one of the effects that is detrimental to power could easily swamp any smaller effect that would usually be helpful.
If the A port has already a large wall or septum dividing it off from the main port - then I can see that any advantage from the lifted floor via a reduction in short circuiting would be minimal.
Creating a high dam at the port, by inference then means we get back to having a very tapered "diffuser" like duct, with a much bigger exit area than that at the entry point. And as is well documented, the exact reverse makes better power.
In this case the sim is not very helpful in determining what is optimum, as it takes no account of the change in short circuiting efficiency, only the flow effects on the Mach numbers of the area changes.
Then lastly we have the thermal issue of the insert overheating, due to lack of an efficient heat path to the cooler water or finned cylinder.
Very much a can of worms, not easy to sort the positive effects and be able to identify any general pointers to guide other tuners.
Hey TeeZee, as a favour can you try a radius on the leading edge of floor dam, before you do anything else.
Be interesting to see if that helps the outflow Cd sufficiently to increase power, and wont affect the A port short circuiting efficiency at all.
318101 318098
Radius edge on the exhaust port dam
318102
Red = radius on the leading edge of the exhaust port dam, Blue = sharp edge.
Radius is better.
318103
Red = radius edged dam, Blue = No Dam.
Making progress, so what is the next step, suggestions welcome.
seattle smitty
22nd December 2015, 18:07
Funny thing, that mirror-polishing piston crowns, one of the oldest tricks in the racing engine-builder's bag, dating from the Thirties and possibly earlier, a technique that COSTS NOTHING (compare with ceramic coatings!) but a little time, is done by very few. Every engine I've built in the last forty five years, from lawn mowers and chainsaws, to Onan twins for welder/generators, to family cars and trucks, ALL of them get polished pistons . . .
. . . AND of course, port clean-up always, even the lawn mowers!!:yes:
Once a 2-stroker, always a 2-stroker; a friend still is telling a story on me of coming into my shop where I was "porting" (removing sharp internal edges) a brand new shop vacuum for a little better suction . . . or just because the urge to grind overcame me, LOL. Well, I might save time in other areas (no television). I hope you'll tell me I'm not the only one with this compulsion.
At risk of momentarily creating a silly distraction in TeeZee's thread, shouldn't there be a coat-of-arms for 2-strokers; what elements should we include? One guy suggested our universal symbol should be a piston with a big ugly skid-mark down the side. I would add crossed flex-shaft Foredom right-angle grinding handpieces. Ideas??
Anyway, wishing y'all a good holiday.
SwePatrick
22nd December 2015, 20:07
If the ignition miss fires with resistors then it hasnt sufficient power - drop the spark gap to less than 0.5mm
Tried that already. =(
speedpro
22nd December 2015, 21:45
When people say the resistor cap or wires causes a misfire there is a serious problem. Lets say the resistance is 5K. The current may be 20-50mA, I don't really know. Ohms law says E=IR so E=.02X5000=100v or E=.05X5000=250v. Subtracting 100v or 250v from the 20,000v thrown at the spark gap is .5-1.25% less voltage. Yes I realize there is a bit more to it but in all reality it should make next to no difference.
SwePatrick
22nd December 2015, 22:47
Yes!
Somehow it made the difference for me.
But i´ll measure things up, i just swapped to the std cable,cap that came with PVL when i bought it.
And at the same as i wanted to test non resistor system, i swapped the plug to an oldschool b9hs plug ;)
I still had it working earlier with resistorsystem, something has fouled for me.
I´m at this point in the middle of sorting this out.
Ignitionpower is measured in Joule?
Frits Overmars
23rd December 2015, 00:40
a friend still is telling a story on me of coming into my shop where I was "porting" (removing sharp internal edges) a brand new shop vacuum for a little better suction ...
I hope you'll tell me I'm not the only one with this compulsion.You're not.
Merry Christmas to all :D.
teriks
23rd December 2015, 03:27
Making progress, so what is the next step, suggestions welcome.
Well, the original plan of lowering it a bit at the time makes sense.
Personally Id go a slightly different direction, if I had the time and resources that is.
-My next step would be a varying radius on the dam, making a full round at the center of the port and leaving the ends as is.
Something like this:
318116
After that, back to your original plan.
peewee
23rd December 2015, 04:05
Teriks with the center rounded and sides left as is up high you must meen like the latest generation KTM 250. I'm sure there's a port map of it around here
teriks
23rd December 2015, 04:24
Teriks with the center rounded and sides left as is up high you must meen like the latest generation KTM 250. I'm sure there's a port map of it around here
I don't know, haven't seen the latest KTM250 cylinder.
2005bully
23rd December 2015, 04:43
You're not.
Merry Christmas to all :D.
It seems this forum has made many of us not so alone anymore. Merry Christmas to one and all.... Kermit Buller
ief
23rd December 2015, 06:13
Dykes rings are discussed only a couple off times and it seems they are not favorable. For one they cause detonation earlier than normal ring as I understand. Still, I'm gonne use some pistons with said rings. Now I wonder, are they more prone to 'bite' in the ex port when going to say 70 % What else should be taken into consideration?
And on a sidenote, is it a big problem if the ring-gap goes over a small port and if not, what would be considered small? (39 mm bore in this case) My thinking was if I have, say a, 7 mm wide port there no way for the ring to catch that.
adegnes
23rd December 2015, 06:20
Dykes rings are discussed only a couple off times and it seems they are not favorable. For one they cause detonation earlier than normal ring as I understand. Still, I'm gonne use some pistons with said rings. Now I wonder, are they more prone to 'bite' in the ex port when going to say 70 % What else should be taken into consideration?
And on a sidenote, is it a big problem if the ring-gap goes over a small port and if not, what would be considered small? (39 mm bore in this case) My thinking was if I have, say a, 7 mm wide port there no way for the ring to catch that.
Ring gap passing over a 7mm wide port in 39mm bore = no problem at all.
I had the gap pass over one of the b-ports in this cylinder - not exactly ideal, but it didn't snag. (chipped nikasil is from porting mishap).
318117
wobbly
23rd December 2015, 07:43
Looking at the pics my first reaction is to " fix " the insert - that is extend the floor all the way out to the flange face.
As I said earlier having the dam in place makes the exit area much bigger than that at the port - and we already know that the reverse
scenario makes better power.
Having a much smaller area at the port may in fact work really well if the whole duct is reduced to suit, keeping the Mach number higher right down to the header.
TeeZee, try putting the measured data into EngMod and have a look at the Mach, down the duct length by varying the position of the Ex sensor.
Test it as it is now, then make the exit area much smaller as well - the power thrown up will be an indication of the result,but the Mach number gives us some insight into the actual effect.
In this case, maybe having a much smaller duct vol, with steps, like an old RS125, at the header, just might be a nice Xmas prezzy.
To make the sim really accurate, you will need to specify an actual step in the pipe input, as this has a big affect on the in and outflow calculations.
On a personal note, I am really glad we have now got back to the important shit of discussing 2T technology, and we have got rid of the idiot commentators suggesting I should
stop posting my thoughts on what and how these things work as HRC knows everything ( one of the stupidest things I have ever seen in print ) and I ( or anyone ) cant possibly be able to improve on anything they did.
If I was allowed I would have the dyno running on Xmas day to continue to learn how to improve on what Honda did - but then I would have to also be making my own Xmas pudding, not my job or forte.
Merry Xmas to you all and I hope the fat bearded guy drops off something cool for everyone here.
Martin1981
23rd December 2015, 07:50
thanks wob and merry christmas to you and all the others. try to forget the stupid idiots allthough it is hard. the world is full of them:facepalm:
emess
23rd December 2015, 11:52
I am really glad we have now got back to the important shit of discussing 2T technology
oh yes!
I think now is as good a time as any to say a huge thanks to all that have contributed so much on this thread. To Rob (TeeZee) for showing all his experiments regardless of whether they work or not and especially to Frits and Wobbly - your insights, expertise and time you spend helping us are all massively appreciated.
:clap: :clap: :clap: :clap:
Merry Christmas & a Happy high powered New Year to all.
Mick
ief
23rd December 2015, 12:10
Driving force, TZ, hat's off mate... happy stuff to all of you and what not (not a big fan of the hollydays)
F5 Dave
23rd December 2015, 12:20
Indeed seasonal greetings and thanks for all the knowledge gifted by contributors.
Me? I'm hoping for a new impeller shaft for my gasgas. As the distributor in the loop is Triumph nz I might be asking for a Christmas miracle.
wobbly
23rd December 2015, 17:05
The arc over voltage to ionise the spark gap can be as much as 40Kv, but once this has occurred the burn period where the Joules stored in the cap are drained away
in forming the ignition kernel is typically as low as 10Kv in a CDI system.
In most cases we should have a 5K plug as well as a 5K cap in series , thus we have a 10K resistance.Running the formula again this gives a loss of 2% or 5%.
As most CDI wiith source coils have very limited Joules available due to lots of turns needed to create voltage - not current, this i believe is significant.
DC/DC converters are a completely differing scenario, where Joules and or voltage are easy to generate, individually or in tandem.
TZ350
23rd December 2015, 17:32
Looking at the pics my first reaction is to " fix " the insert - that is extend the floor all the way out to the flange face.
As I said earlier having the dam in place makes the exit area much bigger than that at the port - and we already know that the reverse scenario makes better power.
Having a much smaller area at the port may in fact work really well if the whole duct is reduced to suit, keeping the Mach number higher right down to the header.
Thanks, it is a team effort, hopefully Chambers will be happy to continue the experiment because he is the one doing all the real work making the changes.
I only help by recording the dyno runs and posting the results. I am looking forward to adding to the Team ESE stable by completing my own 50 with the information we find out from Chambers efforts.
peewee
24th December 2015, 15:32
hey guys i been slowly working on a new project and as it is right now the radiator is mounted slightly in front of the center of the chassis and in front of the engine (open chassis with no fairings) but there is no shielding on the radiator to catch any air. i was thinking to use some shielding on all four sides of the rad. maybe i can just use some stiff sheets of plastic or even weld some thin alluminum together to form a box shape that attaches to the rad sides/top/bottom. would it be affective if the walls were only say 6" long forward , and how much inward angle would each wall need to be ? i didnt really want to spend alot of time making something super elaborate but if i could keep it simple and affective it would be nice. i may even use a fan on the back side of the rad but i first want to sort out some kind of rad ducting, assuming this ducting idea is even worth bothering with. what im talking about is like the photo. right now my rad is like the top example but i want to make it like the bottom one but i was thinking using four walls instead of two like the photo
husaberg
24th December 2015, 15:35
hey guys i been slowly working on a new project and as it is right now the radiator is mounted slightly in front on the center of the chassis and in front of the engine (open chassis with no fairings) but there is no shielding on the radiator to catch any air. i was thinking to use some shielding on all four sides of the rad. maybe i can just use some stiff sheets of plastic or even weld some thin alluminum together to form a box shape that attaches to the rad sides. would it be affective if the sides were only say 6" , and how much inward angle would each wall need to be ? i didnt really want to spend alot of time making something super elaborate but if i could keep it simple and affective it would be nice. i may even use a fan on the back side of the rad but i first want to sort out some kind of rad ducting, assuming this ducting idea is even worth bothering with
I would suggest you Buy this book.
http://ecx.images-amazon.com/images/I/51OWcEUiJNL._SX258_BO1,204,203,200_.jpg
The Racing Motorcycle - A Technical Guide John Bradley it looks like its available for download as well.
peewee
24th December 2015, 15:48
i see there is vol 1 and 2. would i be better off with 2 ?
husaberg
24th December 2015, 15:55
i see there is vol 1 and 2. would i be better off with 2 ?
Both but Volume 2 I have not read as its out of print.
Pretty sure volume 2 is more practical fabrication skills.
Volume 1 is theory and design mainly. It has a good section on ducted cooling
richban
24th December 2015, 16:07
Merry Xmas to all and thanks again for all the amazing information shared on this Thread. I am sure It's made a massive difference to anyone racing a 2 stroke in NZ or anywhere across our small planet for that matter. Well done Rob!
We will be flying the 2 stroke flag again this year at the cemeterycircuit on boxing day. ( www.cemeterycircuit.co.nz ) This time with 3 bikes. 3 x NSR300's There is live streaming if you want to take a look. F3 is where we will be.
Live timing. http://www.livetiming.co.nz/Live_Timing.aspx
Cheers RB.
mr bucketracer
24th December 2015, 16:19
Merry Xmas to all and thanks again for all the amazing information shared on this Thread. I am sure It's made a massive difference to anyone racing a 2 stroke in NZ or anywhere across our small planet for that matter. Well done Rob!
We will be flying the 2 stroke flag again this year at the cemeterycircuit on boxing day. ( www.cemeterycircuit.co.nz ) This time with 3 bikes. 3 x NSR300's There is live streaming if you want to take a look. F3 is where we will be.
Live timing. http://www.livetiming.co.nz/Live_Timing.aspx
Cheers RB.thanks for the link , you should do well there , love that track , next year
nick gill
24th December 2015, 17:04
On a personal note, I am really glad we have now got back to the important shit of discussing 2T technology...
Hi all.
Long time lurker and long time learner here (I've read all the posts), but I want to pipe up [pun!] to say thanks to all the contributers here, and especially to the fine judgement of most who know when to shut up and listen, and when to make noise. Long may the learning and sharing continue.
Wob, a few pages back you were saying the Lectron can be heavily inclined due to the layout of the idle circuit.
I've attempted to convert the Mikuni TM34SS into a downdraft with modified float bowl, pump around fuel level, and jet pick-ups. I could never get it to run lean enough although the various scavenge placements I tried all worked very well. Now suspect the idle circuit was the cause as you describe.
With your in-depth familiarisation with these carbs, can you forsee a fix for this?
Dell'orto achieved what I'm aiming for with the Gilera 125/250 Twin factory racers. Can anyone elaborate on the inner workings of these special carbs or how I could emulate them?
https://farm2.staticflickr.com/1583/23311551913_80d2acbdf2_c.jpg
https://farm6.staticflickr.com/5657/23830063532_0984fff310_c.jpg
https://farm2.staticflickr.com/1607/23570470399_8c16510715_c.jpg
F5 Dave
24th December 2015, 19:19
Hey Rich Rich and Sketch. Good luck and see you in the pits.
TZ350
24th December 2015, 21:22
318147
From Team ESE, merry Christmas everyone ...
318136318150318148318149
And have fun with the gift giving, enjoy it all.
318135
Then get on your bike, ride whatever you've got and have a great new year.
husaberg
24th December 2015, 22:03
Hi all.
Long time lurker and long time learner here (I've read all the posts), but I want to pipe up [pun!] to say thanks to all the contributers here, and especially to the fine judgement of most who know when to shut up and listen, and when to make noise. Long may the learning and sharing continue.
Wob, a few pages back you were saying the Lectron can be heavily inclined due to the layout of the idle circuit.
I've attempted to convert the Mikuni TM34SS into a downdraft with modified float bowl, pump around fuel level, and jet pick-ups. I could never get it to run lean enough although the various scavenge placements I tried all worked very well. Now suspect the idle circuit was the cause as you describe.
With your in-depth familiarisation with these carbs, can you forsee a fix for this?
Dell'orto achieved what I'm aiming for with the Gilera 125/250 Twin factory racers. Can anyone elaborate on the inner workings of these special carbs or how I could emulate them?
]
Two bikes I can think of and plenty of Car Carbs have gotten around this
Suzuki Wolf/Stinger
http://www.cmsnl.com/suzuki-t125ii-1971-r-usa_model16254/partslist/85219.html#results
318137318138318139318140318141318142
Humble Honda Stepthrough.
http://images.powersportsnetwork.com/fiche/images/Honda/1971/Motorcycles/1869_CARBURETOR.gif
http://i34.photobucket.com/albums/d136/Xrarespares/c50carbright.jpg
http://i23.ebayimg.com/01/i/000/f3/fd/5c28_35.JPGhttp://i34.photobucket.com/albums/d136/Xrarespares/c50carbleft.jpg
for the car carbs have a good look at the internals for the Webber DCOE vs IDA
http://www.racingbeat.com/images/items/350x280/16601.jpg
http://www.carburetion.com/images/weber/4-45DCOEb.jpg
or the very similar Dellotto equivients
Frits Overmars
24th December 2015, 23:56
I would suggest you Buy this book.I would suggest you buy this book:
318156
It won't tell you anything about cooling air guidance but it will look nice on your bookshelf :D.
Frits Overmars
25th December 2015, 00:04
Dell'orto achieved what I'm aiming for with the Gilera 125/250 Twin factory racers. Can anyone elaborate on the inner workings of these special carbs or how I could emulate them?
https://farm2.staticflickr.com/1607/23570470399_8c16510715_c.jpg
You can build your own:
318145 318144 318146
AndreasL
25th December 2015, 02:24
You can build your own:
318145 318144 318146
Wonder if a simple wedged spacer between carb and bowl on my Mikuni VM would allow for a steeper angle then the 18-20* max stated by Mikuni? Have to take a more careful look inside and see what more that might need to be altered.
Any input how to modify the VM is welcomed.
2005bully
25th December 2015, 03:36
Dykes rings are discussed only a couple off times and it seems they are not favorable. For one they cause detonation earlier than normal ring as I understand. Still, I'm gonne use some pistons with said rings. Now I wonder, are they more prone to 'bite' in the ex port when going to say 70 % What else should be taken into consideration?
And on a sidenote, is it a big problem if the ring-gap goes over a small port and if not, what would be considered small? (39 mm bore in this case) My thinking was if I have, say a, 7 mm wide port there no way for the ring to catch that.
Conventional wisdom seems to say that "L" shaped Dykes rings have become obsoleted by current technology. But for some applications they offer advantages over more modern rings. Their down sides are well known....Prone to detonation, tightening in the groove from carbon buildup, etc. etc,. But on the up side they require lower ring tension and generally offer an ability to pass over wider port widths. Study's of heat dissipation from the piston crown conclude that 60% to 80 % of the heat from combustion in the piston crown is transferred out through the piston rings. In light of this perhaps the improved heat dissipation of the L ring is its largest asset. An additional L ring trait, is that smaller deviations of bore size result in greater amounts of twist than with a conventional ring. Because of this it is good practice to never file down an over sized dykes ring to fit in a smaller bore. Kermit Buller
Here are a couple of links to more information.
http://www.bridgestonemotorcycle.com/documents/l-ring_effect6.pdf
http://www.riken.co.jp/english/pistonring/technology/conductivity.html
seattle smitty
25th December 2015, 06:03
Given its quite squared-off top edge, an edge which is always tight against the cylinder wall, my notion has been that one trait of a Dykes ring (fitted so that its top edge is even with the piston crown) should be that it gives the most crisp, well-defined exhaust port opening point . . . yes? no? . . . for what that might be worth.
Maybe another trait of that type of ring, in that area by the exhaust port, is that it's harder to melt cast iron than the edge of an aluminum piston . . .
(I'm not advocating for or against these rings, just sayin' they might have a couple of useful properties. I raced an engine that had them, long ago, with no problems, but didn't "prove" anything one way or other).
husaberg
25th December 2015, 07:50
My own feeble understanding is the dykes ring offers a greater seal this strength is also its greatest weakness as it provides far more friction and in turn wears out the cylinder very fast.
wobbly
25th December 2015, 08:08
The issue you are up against is that the traditional layout dictates that the idle jet ( and its supply well ) are in front of the slide ( engine side ).
The Lectron has no idle circuit at all, with all the fuel entering the venturi up the main ( emulsion tube - but not ) needle well.
With this old school setup the fuel level for this circuit becomes progressively closer to the exit hole in the floor of the venturi, as the carb is tipped upward.
If you go too high, fuel will simply run straight up the well and dribble into the venturi in front of the slide, with no air flow needed.
To make matters worse this fuel level rises in the front side of the bowl under brakes, again fuel spews out the idle circuit without any vacuum.
Best example of this is a TZ350, where plenty of power gain is to be had by shaving off the rubber manifold face to straighten out the intake by
re angling up the old VM38mm carbs.
Go greater than about 5* and its impossible to stop the flooding under brakes, no matter how low you drop the fuel level by shutting off the float valves early.
The only way I know to get around this is to use the OEM carbs made by Keihin on things like NSR400 etc where the bowl is kept horizontal,and the venturi is angled.
People on here can tell you several other models that had the downdraft carbs from the factory - for exactly the reasons above.
The other example is an FCR as was designed for the heavily downdrafted ports on big 4T engines.
There are quite a few sizes availble in the OEM carbs used by Honda with a D shaped venturi, and the FCR is made in plenty of sizes as well, but jets for this
are a nightmare to size for a 2T.
Dellorto have made some carbs with the idle jet ( and its fuel well ) on the intake trumpet side , with drillings down the side of the emulsion tube and around in front
of the slide.They usually have a fuel adjuster screw on the side, not an idle air screw.
These could easily be modified to run seriously downdraft, as the greater the angle the lower the fuel gets in relation to the actual idle jet height.
ief
25th December 2015, 08:14
Cheers guys, found one of them pdf's as well. I guess they will be fine for my purpose then, street use, cast iron AC, tuned a bit.
Obsolete...hmm. nos pistons from 1965, that figures :)
Ok, back to engmod it is, tnx again!
Grumph
25th December 2015, 08:38
Most of the Dellortos made since the intro of the PHF series have the idle jet on the intake side and can be easily run at up to 45 degrees inclination.
The downdrafts pictured earlier would appear to be based on the basic PHF style bodies. Anyone got any pics of them without the bowls fitted ?
Amusingly enough, the AMAL concentric series, both 1 & 2, have the same setup and are quite good at steep downdrafts.
peewee
25th December 2015, 14:22
I would suggest you buy this book:
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It won't tell you anything about cooling air guidance but it will look nice on your bookshelf :D.
i didnt know you wrote any books, especially about 4t. now if you could talk jan into writing a book :laugh:. anyways what do you think about this photo ? probly wouldnt be to difficult to make something similar and plastic welding guns are dirt cheap
MotleyCrue
25th December 2015, 16:13
Lectron makes a true 90 degree downdraft carb and has for at least a handful of years. I can't recall ever seeing them on their website but they are used on micro/mini sprint applications where people remove their EFI and install downdraft Lectrons. 600cc 4 stroke superbike engines.
Frits Overmars
25th December 2015, 20:17
Study's of heat dissipation from the piston crown conclude that 60% to 80 % of the heat from combustion in the piston crown is transferred out through the piston rings.That may certainly be true for four-stroke engines (unless the piston is cooled from the underside via oil squirting or internally via an oil gallery) and it may also have been true in 1973 when the above-mentioned paper was released, but Jan Thiel found that in the Aprilia engines the transfer streams were the main source of piston cooling.
i didnt know you wrote any books, especially about 4t. now if you could talk jan into writing a book :laugh:. anyways what do you think about this photo ? probly wouldnt be to difficult to make something similar and plastic welding guns are dirt cheapThat book of mine was not especially about foul-strokes; it was about motorcycle maintenance in general; the cover picture was chosen by the publisher.
Jan and I had plans to write a book a long time ago but a friend in the know calculated that we would have to write it in both english and italian in order to cover the costs, and I did not fancy that; it would have cost me a lot of time that I prefered to use for ongoing projects.
The cooling air duct in your photo seems rather abrupt to me but in any case I too would choose plastic over aluminium.
AndreasL
26th December 2015, 01:38
Thanks wobbly,
That was my concern and I'm starting to think that my never ending chase for smaller and smaller idle jets my be caused by a to steep carb angle.
Planing on reducing the inlet length so will have a look to see if it's possible to decrease the tilt some.
Opposite to what I really want...
G Jones
26th December 2015, 03:44
Assuming this ducting idea is even worth bothering with. what im talking about is like the photo. right now my rad is like the top example but i want to make it like the bottom one but i was thinking using four walls instead of two like the photoI'd say effective ducting is one of the best things you can do - if you have a surplus of cooling - you can always "lose" some of it when necessary - can't easily do much to increase cooling without larger rad...
I spent a lot of time on the rad intake when I built our new chassis - also incorporates fresh air intake for the airbox
https://scontent.fman1-1.fna.fbcdn.net/hphotos-xlp1/v/t1.0-9/12072584_953302681382346_1434275134756845364_n.jpg ?oh=464cc7a2ac13f37058e3c46390af9200&oe=57063890
The fairing forms the top of the duct & ensures no air escapes - if air goes in - it has to go through the rad to get out.
On our first outing the temperature was 90 degrees on the day - I ran 2 x temp gauges - to and from the rad - highest we saw on those was 57 degrees - in the past - we'd more likely be seeing 70 - 75 degrees - way hotter than we wanted.
https://scontent.fman1-1.fna.fbcdn.net/hphotos-xlt1/v/t1.0-9/12036901_953302398049041_6336801927193964632_n.jpg ?oh=786d2c1dc494b76fc9e769516cc4de6f&oe=5705D238
Definitely recommend the Bradley books too - if you can get hold of them - the 2nd one has the theory put into practice - still not short of technical knowledge though.
https://scontent.fman1-1.fna.fbcdn.net/hphotos-xta1/v/t1.0-9/12065496_953333778045903_6989469646831434253_n.jpg ?oh=172e0440c06f384e8a88519b5c4c3aad&oe=5720055F
peewee
26th December 2015, 06:43
nice work jones. i figured having no ducting on the rad was the worst thing i could do. soon as i can ill get some photo of the chassis and the rad location and maybe you smarter guys can give me some ideas what direction to go. my experience of air ducting is alsmot zero
i just noticed you mentioned airbox also. alot of people dont bother and just use open filters attached to the back of the carb but i was thinking of experimenting with a airbox of some kind. ill get photos so you can see what my options are
teriks
26th December 2015, 08:05
Inspired of the discussion on ducting of radiators, here something for those still interested in air-cooling, TZ perhaps?
Skip to section two, but spend some time to find the referenced NACA reports later, they are good reading too.
318160
EDIT: Keep in mind that the paper refers to engines with a huge fan in-front, also called a propeller..
1948rod
26th December 2015, 08:20
thanks to all for such great info. from my small experience [super charged vw hillclimber] the weir in the float bowl has to be much bigger than the inlet. the inlet flow should be gradual into the bowl [possibly over a chinamans hat] so as to not influence flow to the outlet or fuel pickup to jets. mota. [available from IWT in aust.] has a new program which will give pipe dimensions for your engine in the chosen rev range. i have been building some pipes for speedway karts which seem to be working ok. my dyno is out of action so cant verify the results. have a great new year in 2t land.
G Jones
26th December 2015, 11:02
i just noticed you mentioned airbox also. alot of people dont bother and just use open filters attached to the back of the carb but i was thinking of experimenting with a airbox of some kind. ill get photos so you can see what my options areA few more photos of the airbox
http://maplesigns.co.uk/photogallery/thumbnails.php?album=34
not quite complete there - and i still need to make a better seal behind the cylinder - I have run an airbox for a long time - but with this latest one - I spent a lot more time trying to get it to seal - almost impossible to get a complete seal but getting close - apart from the "forced air" from the intake - I'm hoping the isolation of the carbs from hot air from the cylinders will help.
Only had a quick peek at that "Design for optimum cooling efficiency" download - will give it a good read when i have a bit more time...
With the restrictions of the bodywork on the sidecar - I had to get the "feed" duct in where there is space - not ideal - but it does push a lot of air through to the airbox (I'll explain how I found out if i can get past the embarrassment)
Haufen
26th December 2015, 11:03
hey guys i been slowly working on a new project and as it is right now the radiator is mounted slightly in front of the center of the chassis and in front of the engine (open chassis with no fairings) but there is no shielding on the radiator to catch any air. i was thinking to use some shielding on all four sides of the rad. maybe i can just use some stiff sheets of plastic or even weld some thin alluminum together to form a box shape that attaches to the rad sides/top/bottom. would it be affective if the walls were only say 6" long forward , and how much inward angle would each wall need to be ? i didnt really want to spend alot of time making something super elaborate but if i could keep it simple and affective it would be nice. i may even use a fan on the back side of the rad but i first want to sort out some kind of rad ducting, assuming this ducting idea is even worth bothering with. what im talking about is like the photo. right now my rad is like the top example but i want to make it like the bottom one but i was thinking using four walls instead of two like the photo
thanks for the picture, peewee.
Can anyone recommend a ratio between the entry area of the duct and the area at the average motorcycle radiator (or airbox)? Or some literature on this subject?
Lightbulb
26th December 2015, 11:22
Inspired of the discussion on ducting of radiators, here something for those still interested in air-cooling, TZ perhaps?
Skip to section two, but spend some time to find the referenced NACA reports later, they are good reading too.
318160
EDIT: Keep in mind that the paper refers to engines with a huge fan in-front, also called a propeller..
Thanks, that is an interesting article . Interesting about the paint thickness and the heat dissipating ability. I saw some tests done with anodising aluminium heat sinks and painted. The anodised was worse than the plain ali. It acts like an insulator.
Air ducting is interesting for sure and not always what I thought it would be. I saw a model with an airgap of 0.75mm around the tuned pipe at it's biggest diameter. I thought it was no where near enough, but the designer said the calculated area was still 60% larger than the air inlet area.
Neil
teriks
26th December 2015, 12:06
Only had a quick peek at that "Design for optimum cooling efficiency" download - will give it a good read when i have a bit more time...
Wont be of much use for your water cooled stuff anyway, so don't waste too much time there. :)
Thanks, that is an interesting article . Interesting about the paint thickness and the heat dissipating ability. I saw some tests done with anodising aluminium heat sinks and painted. The anodised was worse than the plain ali. It acts like an insulator.
Air ducting is interesting for sure and not always what I thought it would be. I saw a model with an airgap of 0.75mm around the tuned pipe at it's biggest diameter. I thought it was no where near enough, but the designer said the calculated area was still 60% larger than the air inlet area.
NeilEven though the area was larger such a section is probably a restriction anyway, due to the huge amount of wall in that narrow flow area.
Perhaps Frits could write a word or two on that? I suspect he don't have to find the proper literature to learn how to perform a calculation like I would have to ;)
husaberg
26th December 2015, 18:00
The issue you are up against is that the traditional layout dictates that the idle jet ( and its supply well ) are in front of the slide ( engine side ).
The Lectron has no idle circuit at all, with all the fuel entering the venturi up the main ( emulsion tube - but not ) needle well.
With this old school setup the fuel level for this circuit becomes progressively closer to the exit hole in the floor of the venturi, as the carb is tipped upward.
If you go too high, fuel will simply run straight up the well and dribble into the venturi in front of the slide, with no air flow needed.
To make matters worse this fuel level rises in the front side of the bowl under brakes, again fuel spews out the idle circuit without any vacuum.
Best example of this is a TZ350, where plenty of power gain is to be had by shaving off the rubber manifold face to straighten out the intake by
re angling up the old VM38mm carbs.
Go greater than about 5* and its impossible to stop the flooding under brakes, no matter how low you drop the fuel level by shutting off the float valves early.
The only way I know to get around this is to use the OEM carbs made by Keihin on things like NSR400 etc where the bowl is kept horizontal,and the venturi is angled.
People on here can tell you several other models that had the downdraft carbs from the factory - for exactly the reasons above.
The other example is an FCR as was designed for the heavily downdrafted ports on big 4T engines.
There are quite a few sizes availble in the OEM carbs used by Honda with a D shaped venturi, and the FCR is made in plenty of sizes as well, but jets for this
are a nightmare to size for a 2T.
Dellorto have made some carbs with the idle jet ( and its fuel well ) on the intake trumpet side , with drillings down the side of the emulsion tube and around in front
of the slide.They usually have a fuel adjuster screw on the side, not an idle air screw.
These could easily be modified to run seriously downdraft, as the greater the angle the lower the fuel gets in relation to the actual idle jet height.
I thought you might like this Wayne,
A pumper carb radio control mixture set up a perfect xmas present for the tuner that has everything...........
Note the highspeed lean out limiting.
http://eknclassic.com/viewtopic.php?p=731208&sid=468dd58870df96cc959957e226d8aeda
peewee
26th December 2015, 19:54
A few more photos of the airbox
http://maplesigns.co.uk/photogallery/thumbnails.php?album=34
not quite complete there - and i still need to make a better seal behind the cylinder - I have run an airbox for a long time - but with this latest one - I spent a lot more time trying to get it to seal - almost impossible to get a complete seal but getting close - apart from the "forced air" from the intake - I'm hoping the isolation of the carbs from hot air from the cylinders will help.
Only had a quick peek at that "Design for optimum cooling efficiency" download - will give it a good read when i have a bit more time...
With the restrictions of the bodywork on the sidecar - I had to get the "feed" duct in where there is space - not ideal - but it does push a lot of air through to the airbox (I'll explain how I found out if i can get past the embarrassment)
did you do prior calculations for the airbox size, like 10x engine capacity etc, or did you just make it as big as the available chassis space would allow ? i heard theres some theory on how big the box should be but i cant remember the details
Frits Overmars
26th December 2015, 23:05
That paper on air cooling is great, as usual with NACA publications. But I stumbled upon one paragraph that cries for some comment:
You only need to get rid of heat that stays behind. Insulating coatings in the combustion chamber will stop heat transfer to
the engine...I remember reading somewhere else that a ceramic coating of the combustion chamber would have a dramatic effect on
lowering heat transfer to the cylinder head, and greatly improve efficiency of the engine cooling system."You only need to get rid of the heat that stays behind". Yeah, and then you only need to get rid of the massive detonation caused by the high surface temperatures inside the combustion chamber.
Next point: a ceramic coating would in no way improve the efficiency of the cooling system; it would merely reduce the amount of heat that has to be moved away.
Air ducting is interesting for sure and not always what I thought it would be. I saw a model with an airgap of 0.75mm around the tuned pipe at it's biggest diameter. I thought it was no where near enough, but the designer said the calculated area was still 60% larger than the air inlet area.
Even though the area was larger such a section is probably a restriction anyway, due to the huge amount of wall in that narrow flow area. Perhaps Frits could write a word or two on that? I suspect he don't have to find the proper literature to learn how to perform a calculation like I would have to ;)You are dead right about the unfavorable ratio between the cross flow area and the wall surface, Teriks. But finding the literature is not the problem.
The problem is knowing how well the air flow can attach to this surface. And that depends on factors like surface roughness, flow velocity, static pressure in the system and the amount of turbulence with which the air enters the system. In short: the problem is insufficient information (as usual).
did you do prior calculations for the airbox size, like 10x engine capacity etc, or did you just make it as big as the available chassis space would allow ? i heard theres some theory on how big the box should be but i cant remember the detailsThe details are not too difficult Peewee. Some dedicated computer programs can calculate the ideal set of circumstances for a nice Helmholtz resonance,
but in general it comes down to this: if you make it as big as the available space allows, it's almost big enough.
G Jones
26th December 2015, 23:18
I did spend (way too much) time reading on the subject - but as it turns out - you can only fit what there is available space for...
I picked up a barely used rad from a guy that had some bad overheating with it - whoever built it had the inlet in the top left & outlet in the bottom left side - so i figured it was short circuiting without actually cooling - I blanked off the outlet & made a new header for it making it double pass (I hope) so forcing all coolant to go down the one half & back up the other to get maximum cooling.
I then tried to concentrate on getting the best seal on the entry - whatever I'd read on entry size didn't much matter - just used what I'd got - and basing my thinking on what we had on the old bike (which worked well enough)
I think you can maybe over think a lot of this (and lots of other stuff too) a lot of the time you can look at something for a while & it's obvious whether it will work or not - main thing I think is to have a duct that has the entry well sealed - if you are scooping air - you don't want it escaping before it's gone through the rad.
All of this took a lot longer than I'd have liked - the original fairing design didn't have the space or the entry where i needed it - so had to make a new fairing - involved a lot of Glass fibre work - making new molds etc but worth the effort - I now have the rad entry I want - and also gives me a lot more space to fit different pipes - there was zero space for any different pipes with the old fairing design.
Just going back to that rad - the guy that had it made - put the inlet / outlet where it was most convenient for the rest of the bike - wrong move I'm afraid - what he should have done is think a bit harder - first - how does this system work - and next - how to adjust the rest of the bike to fall in with that - you can't let not important stuff dictate important stuff !
did you do prior calculations for the airbox size, like 10x engine capacity etc, or did you just make it as big as the available chassis space would allow ? i heard theres some theory on how big the box should be but i cant remember the details
Frits has posted while I was thinking - just shows how much quicker the great mind works ! - I did read up on the subject - whatever I could find - but still comes down to available space - so - the outside of the airbox was made off the inside of the engine cover / seat - couldn't get much more space than that !
husaberg
26th December 2015, 23:34
I did spend (way too much) time reading on the subject - but as it turns out - you can only fit what there is available space for...
I picked up a barely used rad from a guy that had some bad overheating with it - whoever built it had the inlet in the top left & outlet in the bottom left side - so i figured it was short circuiting without actually cooling - I blanked off the outlet & made a new header for it making it double pass (I hope) so forcing all coolant to go down the one half & back up the other to get maximum cooling.
I then tried to concentrate on getting the best seal on the entry - whatever I'd read on entry size didn't much matter - just used what I'd got - and basing my thinking on what we had on the old bike (which worked well enough)
I think you can maybe over think a lot of this (and lots of other stuff too) a lot of the time you can look at something for a while & it's obvious whether it will work or not - main thing I think is to have a duct that has the entry well sealed - if you are scooping air - you don't want it escaping before it's gone through the rad.
All of this took a lot longer than I'd have liked - the original fairing design didn't have the space or the entry where i needed it - so had to make a new fairing - involved a lot of Glass fibre work - making new molds etc but worth the effort - I now have the rad entry I want - and also gives me a lot more space to fit different pipes - there was zero space for any different pipes with the old fairing design.
Just going back to that rad - the guy that had it made - put the inlet / outlet where it was most convenient for the rest of the bike - wrong move I'm afraid - what he should have done is think a bit harder - first - how does this system work - and next - how to adjust the rest of the bike to fall in with that - you can't let not important stuff dictate important stuff !
One thing from bradleys book was he believed the radiator would work better leaning backwards, I can't remember why?
G Jones
27th December 2015, 00:43
One thing from bradleys book was he believed the radiator would work better leaning backwards, I can't remember why?I think you're correct - I spent a lot of time reading John's book - but it still came down to the "available space" - I totally hate "compromise" - but sometimes you have to - either that or scrap the project...
I have spent a lot of time reading the "Bradley Books" - I can remember him from over 40 years ago - we were both racing 125 yams at the same time...
seattle smitty
27th December 2015, 07:17
Air-cooled recip airplane engines have "pressure cowlings" intended to force air all the way around and through their close-fitting cooling fins. Seems to me you have the same requirement; your engine is liquid-cooled, but the radiator is air-cooled, and forcing air under pressure through the cooling fins of the radiator calls for a "pressure cowling." The pressurized air can be forced through cooling fins (of whatever kind) at a considerable angle to the airflow into the front of the cowl; think about little airplanes with opposed-four and six cylinder engines where the fins are a full ninety degrees to the air entering the cowl. No, the air doesn't blast into one side of the cylinders; instead it builds pressure and shrouds turn it a full right angle so that it is forced downward around all sides of the cylinders, under pressure, and then flows out underneath the airplane . . . and in better designs is to some extent extracted by a low-pressure area.
Peewee, with this in mind, I'm not sold on the three-part drawing you put up for discussion on P. 1406. The author is inadvertently showing two different effects because his drawings are too simplified. The bottom drawing, supposedly the "best" option of the three, does indicate that you want a non-turbulent airflow around the outside of the radiator shell, which is true enough. But my first problem with the drawing is that he doesn't carry the idea past the widest part of the radiator, when in fact you'd want to carry it as far as you can past that point (ignoring "packaging" problems for the moment). As drawn, the airflow would immediately go turbulent as it tries to re-attach when it passes the widest part of the radiator. What you'd ideally want is, via good fairings, to get the airflow to come together far enough downstream of the radiator that is creates something of a draw on the air coming out of the radiator. This is a whole lot easier to do on a rig like Jones', or a Bonneville streamliner, than on a bucket, but you do what you can.
The second of those three drawings is claimed to be not as good as the third, but why? If the author was making a point about airflow AROUND the radiator, okay. But if he was worried that some of the entry-air would not be used, and would spill out the sides (as he has drawn it), I think that's not a problem. To achieve a pressure-cowling you have to build up a head of pressure, and naturally some of the entry air will spill out. Well, so what? You want that pressure build-up, to force the air between all parts of the fins and tubes. The air-entry openings in front of airplane cowling are pretty small, but airplanes are going relatively fast, and the holes into the pressure cowls are sized for best efficiency.
I think this all is a particular problem for bikes, because with the front tire, forks and braces, maybe a fender, the airflow into, let alone out of the radiator, is going to be pretty haphazard and turbulent, the very opposite of what you'd want to get air pushed, and maybe pulled, through all those little fins and tubes. For that matter, the same problem applies to bikes with air-cooled cylinders. Some old Suzukis had what they imagined to be ram-air partial cowls around the heads. But to be ram-air, they would need air blasting directly into the front of the gizmo; how can this be with the tire and forks making the air eddy around every which way? As much as I like the look of an old-fashioned naked motorcycle, having a cowl lets you duct the air in useful ways.
TeeZee and I exchanged some PMs on this subject some time back, and he has some good ideas about it.
teriks
27th December 2015, 07:54
The second of those three drawings is claimed to be not as good as the third, but why? If the author was making a point about airflow AROUND the radiator, okay. But if he was worried that some of the entry-air would not be used, and would spill out the sides (as he has drawn it), I think that's not a problem. To achieve a pressure-cowling you have to build up a head of pressure, and naturally some of the entry air will spill out. Well, so what? You want that pressure build-up, to force the air between all parts of the fins and tubes. The air-entry openings in front of airplane cowling are pretty small, but airplanes are going relatively fast, and the holes into the pressure cowls are sized for best efficiency.
Most likely because the extra inlet area adds nothing but drag.
From a strict cooling point of view it wont matter though, unless you add something like a front wheel in front of that inlet, then you might want something like #2 after all.
EDIT: So basically I agree with what you said later in your post.. should learn to read to the end before replying ;)
Glad I only have the spinning prop to worry about in front of my intakes..
seattle smitty
27th December 2015, 08:02
EDIT: So basically I agree with what you said later in your post.. should learn to read to the end before replying
Oh man, anybody who finds anything I say worth a comment might want to wait half an hour after I post it, because I frequently spend that long coming back and editing it so it might make sense, doh!!
peewee
27th December 2015, 09:15
smitty if the area behind the rad is low enough pressure then wouldnt the air have no choice but to go through the fins, rather than some of it bouncing back out around any ducting like the photos show ? thats my understanding of it anyways. maybe the inward tilted ducting creates a lower pressure behind the rad. hell i dont know.
what i do know is it wont be feasable for me to use nice fancy fairing and such. well maybe it would be possible with alot of time and thought but i was hoping to keep it somewhat simple but decently affective and thats why i originally posted the rad photo with three different scenarios. depending how much they weigh i was also thinking of a small electric fan on the back side with cowling around it like a car. this project is going to be a methanol drag racer so maybe im over thinking it but still it seems like some sort of ducting will be better than nothing at all. then again maybe no ducting is better than poorly designed ducting. in the meen time ill search the web for info
jones ill have to get some measurments but if my airbox available space is to small maybe ill be better off with no airbox at all. i havent got that far yet but ill report back when i have a better idea of the available space
while im thinking of it, does anyone know of a website with a decent gearing/rpm calculator. i have two sets of primary gears with different ratios that i can use and i wanted to compare the rpm drops through gear changes. so far most of the calculators ive found only show mph differences bewteen gears.
Frits Overmars
27th December 2015, 10:13
i have two sets of primary gears with different ratios that i can use and i wanted to compare the rpm drops through gear changes. so far most of the calculators ive found only show mph differences bewteen gears.The primary ratio has nothing to do with the rpm drops through gear changes. If for example you double the primary ratio, you must halve the secondary ratio in order to reach the same speed at the same revs, but that won't change the ratio steps between the gears.
G Jones
27th December 2015, 10:39
jones ill have to get some measurments but if my airbox available space is to small maybe ill be better off with no airbox at all. i havent got that far yet but ill report back when i have a better idea of the available space OK - you may need a reasonable amount of space - I'd have liked more - but if you can duct an inlet somehow - you'll increase the amount of air available - however - one of the best things about the airbox (at least from my point of view) - is that there is less of the dust & small rocks getting in the engine - completely open carbs always suck in any crap that comes close...
while im thinking of it, does anyone know of a website with a decent gearing/rpm calculator. i have two sets of primary gears with different ratios that i can use and i wanted to compare the rpm drops through gear changes. so far most of the calculators ive found only show mph differences bewteen gears.I have a gearing / speed calculator on my website - it's set up for TZ350 & sidecar wheels - but you could download the script & code - adjust to suit what you need....
wobbly
27th December 2015, 11:13
Here is a simple calculator with tyre size, ratios,rpms as inputs.
With speeds and rpm drops as outputs.
Its setup with a stock TZ350, but can be changed to anything you want.
husaberg
27th December 2015, 11:17
smitty if the area behind the rad is low enough pressure then wouldnt the air have no choice but to go through the fins, rather than some of it bouncing back out around any ducting like the photos show ? thats my understanding of it anyways. maybe the inward tilted ducting creates a lower pressure behind the rad. hell i dont know.
what i do know is it wont be feasable for me to use nice fancy fairing and such. well maybe it would be possible with alot of time and thought but i was hoping to keep it somewhat simple but decently affective and thats why i originally posted the rad photo with three different scenarios. depending how much they weigh i was also thinking of a small electric fan on the back side with cowling around it like a car. this project is going to be a methanol drag racer so maybe im over thinking it but still it seems like some sort of ducting will be better than nothing at all. then again maybe no ducting is better than poorly designed ducting. in the meen time ill search the web for info
jones ill have to get some measurments but if my airbox available space is to small maybe ill be better off with no airbox at all. i havent got that far yet but ill report back when i have a better idea of the available space
while im thinking of it, does anyone know of a website with a decent gearing/rpm calculator. i have two sets of primary gears with different ratios that i can use and i wanted to compare the rpm drops through gear changes. so far most of the calculators ive found only show mph differences bewteen gears.
Here is a simple calculator with tyre size, ratios,rpms as inputs.
With speeds and rpm drops as outputs.
Its setup with a stock TZ350, but can be changed to anything you want.
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130461984#post1130461984
http://www.gearingcommander.com/
This one below have nice graphs as well.
peewee
27th December 2015, 12:46
thnx for the help fellas. frits i thought changing the primary ratio some how made the gear spread wider even though the trans gears remain the same. guess i better do more research as i hardly know anything about this subject. am i reading this chart correct ?
if the shift point is 10,500 at each gear
1-2 would drop to about 6800 , a drop of 3,700 rpm
2-3 would drop to about 8000 , a drop of 2,500 rpm
3-4 would drop to about 8600 , a drop of 1,900 rpm
4-5 would drop to about 8700 , a drop of 1,800 rpm
5-6 would drop to about 8700 , a drop of 1,800 rpm
peewee
27th December 2015, 15:23
Here is a simple calculator with tyre size, ratios,rpms as inputs.
With speeds and rpm drops as outputs.
Its setup with a stock TZ350, but can be changed to anything you want.
thats a nice one and just what i was looking for. aparently theres a newer version now gearing_V12. looks pretty similar but it has stuff listed in mph also
after trying different primary ratios i see what frits was saying about the gear change rpm stays the same. so what would be the purpose or reason to have more than one primary gear set available ? im guessing if you were racing long distance and needed all five gears for alot of top speed vs a short race and only needed three gears
husaberg
27th December 2015, 15:53
thats a nice one and just what i was looking for. aparently theres a newer version now gearing_V12. looks pretty similar but it has stuff listed in mph also
after trying different primary ratios i see what frits was saying about the gear change rpm stays the same. so what would be the purpose or reason to have more than one primary gear set available ? im guessing if you were racing long distance and needed all five gears for alot of top speed vs a short race and only needed three gears
Its all only about gearing.. Use whatever primary gearing gets the gearbox to spin faster to lessen the load on the gearbox and clutch.
ie if you have a choice between say 3.5:1 and 3.0:1 choose 3.5:1
lodgernz
27th December 2015, 16:05
Its all only about gearing.. Use whatever primary gearing gets the gearbox to spin faster to lessen the load on the gearbox and clutch.
ie if you have a choice between say 3.5:1 and 3.0:1 choose 3.5:1
I think you have that back to front Husa. 3.0:1 will spin the clutch faster
husaberg
27th December 2015, 16:26
I think you have that back to front Husa. 3.0:1 will spin the clutch faster
Right you are......Backwards I do have it
https://pbs.twimg.com/media/CWbUYGRUEAAXTu8.jpg
wobbly
27th December 2015, 16:33
In some cases,the RZ/Banshee is a good example, you have to reduce the primary ratio to enable realistic sprockets to be used and achieve the
terminal speed wanted.
This engine has 2.8,2.68,and 2.5 ratios ( in straight cut as well ) from aftermarket suppliers.
peewee
27th December 2015, 16:42
my choices are 2.81 and 2.91. i figured the slower spinning would lessen the load ? whats the theory behind the lesser load. what do you say wobbly, which should i try first ? i have both sets and their straight cut
TZ350
27th December 2015, 18:12
Page 1410 links list to go here when I have compiled it .......
Air/Fuel ratio meter ....
The Lambda I use is from Innovate Motorsports with a Bosch heated wideband, and it can read out in various formats.
It will convert directly to A/F ratio, Lambda Number, or 0-5V, I use the A/F ratio as an input direct to the dyno datalogger so as to see the power overlayed with A/F as well as deto etc.
The probe is in the front of the muffler,with a threaded insert that sits right on top of the perf tube.
It has a gauge reading out A/F, but you for sure havnt time to watch that when doing a dyno run.
is this one you use ?http://www.lectronfuelsystems.com/products/wego_III_O2_sensor_kit.html
Yes that is what I alluded to re tracking EGT with a really fast response probe ( open tip, Stinger from EGT Industries - guaranteed for 2 years ) and datalogging it against power.
If the egt has dropped from say 650 to 600, then it would need at least 2 jets leaner to get back to your baseline.
2 jets is night and day power wise, and peak power rpm wise. And as you well know, if the mid has gone rich in relation to the top,then you will need to adjust the air correction to skew the fuel curve as well.
This is the controller I use for the Lambda,and this sends the A/F corrected numbers to the dyno datalogger - 12.8:1 makes a lot more sense to me than 0.9 Lambda ever did.
http://www.innovatemotorsports.com/products/lc2.php
Knock Sensor ... http://www.knockgauge.eu/
Re the knock sensor - there are a dozen different vehicles that use the same Bosch style sensor. BMW,Audi, Infiniti,Subaru etc It has an 8mm thru hole so is ideal to clamp under a lengthened head stud. They use a standard fuel injector plug. After a 10 second look here is one cheap as chips.
http://www.ebay.com/itm/22060-AA070-Knock-Sensor-For-99-02-Subaru-Legacy-Impreza-Outback-Forester-New-/272085556005?hash=item3f59901b25:g:lqYAAOSwstxVVDl 3&vxp=mtr
One wire is earthed, the other is the gauge input. Once its wired up you can tap the bolt head with a hammer and adjust the sensitivity so the yellow lights flicker - then give it a good bash and the red deto light will flash.
Knock sensor. Interesting calculation for detonation frequency (Khz)
http://www.autospeed.co.nz/cms/article.html?&A=0348
my bike should be around 11.4 kHz...
Get one of these with the extra wire to ground. When it sees deto it can ground an Ignitech input and retard the timing automatically. You get flashing lights and engine protection all in one shot, and cheap as chips - made in Czech so it likes being connected to an Ignitech - same lingo..
Works perfectly - when you get it trimmed correctly it will tell you where to manually pull out timing, then it just operates as a failsafe.
http://www.ebay.com/itm/Knock-gauge-for-detonation-sensor-klopfsensor-NEW-/110818862446?pt=Race_Car_Parts&hash=item19cd51a56e&vxp=mtr#ht_1582wt_1297
Bosch Vibration sensors. http://www.bosch.com.au/content/language1/html/4563.htm Wobbly , what is the difference between 2 pole and 3 pole types? Are these available anywhere local, I rang a Bosch distributor in Auck, I think they were giving me the 1000 yard stare on the phone
The 3 pole ones have 3 wires so don't know how these would be connected.
Most are 2 wire and are common to most late model cars, Audi, VW ,BMW, Subi etc, the plug is standard injector type.
Easiest is the one with 8mm hole thru the middle, they are rugged as hell, so rarely bust, whip down to wrecker and get one for jack shit with the plug connected.
Forget the homemade bullshit, get one of these with the extra wire to ground.
When it sees deto it can ground an Ignitech input and retard the timing automatically.
You get flashing lights and engine protection all in one shot, and cheap as chips - made in Czech so it likes being connected to an Ignitech - same lingo..
Works perfectly - when you get it trimmed correctly it will tell you where to manually pull out timing, then it just operates as a failsafe.
http://www.ebay.com/itm/Knock-gauge-for-detonation-sensor-klopfsensor-NEW-/110818862446?pt=Race_Car_Parts&hash=item19cd51a56e&vxp=mtr#ht_1582wt_1297
<tbody>
Knock gauge for detonation sensor klopfsensor
</tbody>
http://www.knockgauge.eu/
263028
Ok mine turned up today.
263027
And a couple of two wire sensors I picked up cheap from the local garage.
Good luck with the Deto sensing TZ. I like the little warning instrument!
Here's how I mounted my sensor. I drilled-tapped an old head bolt and screwed a stud.
263051263052
My sensor has a PN 0-261-231-001, what's yours?
According to this http://www.phormula.co.uk/KnockCalculator.aspx , deto freq for 56mm bore should be 10.2kHz.
According to Bosch datasheets for PN -047 (http://www.bosch-motorsport.de/en-US/literature/en-US/Knock_Sensor_KS-R_Datasheet_51_en_2779074187.pdf) & -120 (http://www.bosch-motorsport.de/pdf/sensors/knock/KS-P.pdf), sensors are able to catch frequencies from 1 to 20 kHz.
I assume all Bosch sensors can sense knock within this range (?)
edit: As for the pick-up voltage, I think it won't be more than +-10V. I had a voltage test yesterday with a data acquisition device in real time! I spinned the crank by hand and recorder the voltage waveform from the pick-up in the PC. As RPM increase, amplitude (and freq of course) of the pulses increase - by hand-spinning it didn't exceed 3~3.5 VAC. Sure it was a lot of fun to watch! :D
263081
BOSCH p/n 0 261 231 046
263082
Other sensors can be found here too. http://www.bosch.com.au/content/language1/html/4563.htm
Relocated the knock sensor. I found some steel head bolts and faced one off, then drilled and tapped it. And made a standoff that was carefully faced off as the knock sensor likes to be securely mounted on a very flat surface. The black goop (silicon glue) on the blue wire is there as a strain relief and hopefully it will stop the vibration breaking the wire where it is attached to the copper head fin.
270747
I have just received another Knock Gauge, this one has two extra outputs. http://www.knockgauge.eu/content/blogcategory/22/41/
YouTube links showing the Knock Gauge in action.
The two green lights, the orange warning light then you see the red det light. http://youtu.be/aZkZR-JBr_E and http://youtu.be/vFoZyw_sHmA
Like last time, one that goes to ground for signaling the IgniTec to retard and a new one that pulses from 0V to +5V each time the Knock Gauge sees a detonation event.
The Curtis event counter can then count the detonations. Now I have the makings of a det sensor, ignition retarder and det counter.
The Trumeter 7111 is no longer stocked by RS but they do have something similar.
269009
703TR002N-512D RS part number 183-5952 $63.50 ... 5-12V and less than 10mA so easily self powered and at 500Hz fast enough to count all deto events as seen by the Knock Gauge or similar, as 200Hz in a 2-Stroke equals 12,000 rpm.
269008
And here is something if you want to try your hand at making a complete det counter for your self.
269011
RS part number 185-6090 $45.30
You could box this along with an amp or frequency filter from Jaycar and make you own little compact det counter.
269012
Electrical specs.
269014
Two different ways to go, with an amp you would count the high amplitude deto peaks or you could use a band or high pass frequency filter and count whatever passes through it.
This post links back to various cheap counters that could be used with the Knock Gauge.
JanBros
27th December 2015, 22:15
my choices are 2.81 and 2.91. i figured the slower spinning would lessen the load ? whats the theory behind the lesser load. what do you say wobbly, which should i try first ? i have both sets and their straight cut
reducing the speed = increasing the torque and higher torques = more load.
so the higher the primary ratio is, the stronger your clutch needs to be to handle the higher torque.
but you also have to consider the available sprockets for your final drive in order to achieve the top speed. Like Wobbly says : changing an RD250LC designed to turn at 160km/h max into a 500cc version that can go 250km/h, there might not be enough space for a big enough front or small enough rear sprocket to achieve 250km/h, so you need to change the ratio's somewhere else to. simplest is the primary because then you change the ratio for all the gears at once. Most expensive is changing all the gears in the gearbox, but than off course you can have the perfect gearbox made for your engine.
TZ350
27th December 2015, 23:02
A couple of interesting reads about 125cc 2T land speed records and the people behind them.
http://kolblsr.blogspot.co.nz/
http://www.canned-ham.com/index.php/history/setting-the-land-speed-record/
Lef16
28th December 2015, 05:53
Hey guys,
I've already have a knock gauge,but I don't know where to find a decent knock sensor.
I've found plenty cheap sensors on ebay but they don't write the mount diameter.
From the pictures i've found a lot of 2 pin sensor(like wob said) but I don't know the actual dia,and most of them don't tell you via a message. :D
So,can you help me?Wob,what type and brand of knock sensor do you use?
Cheers
peewee
28th December 2015, 06:35
reducing the speed = increasing the torque and higher torques = more load.
so the higher the primary ratio is, the stronger your clutch needs to be to handle the higher torque.
but you also have to consider the available sprockets for your final drive in order to achieve the top speed. Like Wobbly says : changing an RD250LC designed to turn at 160km/h max into a 500cc version that can go 250km/h, there might not be enough space for a big enough front or small enough rear sprocket to achieve 250km/h, so you need to change the ratio's somewhere else to. simplest is the primary because then you change the ratio for all the gears at once. Most expensive is changing all the gears in the gearbox, but than off course you can have the perfect gearbox made for your engine.
ah that makes sense about the higher torque. the clutch setups i have are plenty strong so im not concearned about anything breaking. one is cushioned with rubber disks and the other with springs. both are straight cut gears with billet alloy baskets. theres plenty of sprockets available. 10-17 teeth on the front and 40-48 teeth on the rear. i only need to go from 0-70mph or so. also i have billet 2nd gear for when the clutch is released instantly at the start of the race
TZ350
28th December 2015, 06:38
Hey guys, I've already have a knock gauge,but I don't know where to find a decent knock sensor.
Emess has posted some good tips on how to search this thread using Google for the info you need, it is worth a try..... :niceone:
... some may find this useful. Rather than use the site search which usually fails, use Google so to search this site use an ordinary search phrase and after it add
site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)
for example
Frits priceless site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)
or
Frits pisa site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)
the same will work for other sites with the appropriate site address
Mick
Results of a quick Google search for "knock sensor:www.kiwibiker.co.nz"
ESE's works engine tuner - Page 1090 - Kiwi Biker (http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1090) <cite class="_Rm" style="color: rgb(0, 102, 33); font-style: normal; font-size: 14px;">www.kiwibiker (http://www.<strong>kiwibiker</strong>).co.nz/forums/showthread.php/86554-ESE.../page1090</cite>
Jan 18, 2015 - 15 posts - 10 authors http://www.kiwibiker (http://www.kiwibiker).co.nz/forums/at...7&d=1413067504 .... As knock sensors usually only have one wire I guess they are earthed through the ...ESE's works engine tuner - Page 879 (http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page879) 15 posts 29 Nov 2013 ESE's works engine tuner - Page 477 (http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page477) 15 posts 10 Apr 2012
richban
28th December 2015, 07:23
I am pleases to say Glen took the days top spot in F3, with 2 great race wins on the street. And living up to his nickname sketchy, with a few exciting moments for him and the crowd. It has been a very long time since a 2 stroke has won there. Great effort.
I was crap. Bike was great.
318185
TZ350
28th December 2015, 07:39
I was crap. Bike was great.
318185
Oooops .... Crap..... Bugger
But great to hear of Glens 2T win.
wobbly
28th December 2015, 08:36
Hey Rich,there are much easyer ways to check if the front axle is tight.
Re the knock sensor - there are a dozen different vehicles that use the same Bosch style sensor.
BMW,Audi, Infiniti,Subaru etc
It has an 8mm thru hole so is ideal to clamp under a lengthened head stud.
They use a standard fuel injector plug.
After a 10 second look here is one cheap as chips.
http://www.ebay.com/itm/22060-AA070-Knock-Sensor-For-99-02-Subaru-Legacy-Impreza-Outback-Forester-New-/272085556005?hash=item3f59901b25:g:lqYAAOSwstxVVDl 3&vxp=mtr
One wire is earthed, the other is the gauge input.
Once its wired up you can tap the bolt head with a hammer and adjust the sensitivity so the yellow lights flicker - then give it a good bash and the red deto light will flash.
Re the clutch,where you are continually dumping the clutch and putting really big instantaneous loads on the drive train, the sprung hub has proven to be more reliable than rubber discs that eventually
distort permanently.
d2t
28th December 2015, 10:27
I would suggest you buy this book:
318156
It won't tell you anything about cooling air guidance but it will look nice on your bookshelf :D.
Hey Frits, was this book ever published in English? I wouldn't mind another well written book on the shelf to fool my guests into thinking I'm smart.
speedpro
28th December 2015, 18:30
Surely a technical book in a "foreign" language would impress your guests more rather than just another English language tome.
F5 Dave
28th December 2015, 18:53
1/10th of a second earlier in that pic Rich and you would have seen me running. You hit the barrier I was behind. That was one impressive crash and I had that nightmare that night you often get after a big crash but there was a bike cartwheeling towards me.
I'd just recovered and I could see myself back in hospital explaining another motorcycle racing accident but I wasn't riding at the time.
i saw the bike on top of you but I couldn't help due to the fence but you kicked it off ok. At least the thether switch stayed plugged in.
richban
28th December 2015, 19:30
1/10th of a second earlier in that pic Rich and you would have seen me running. You hit the barrier I was behind. That was one impressive crash and I had that nightmare that night you often get after a big crash but there was a bike cartwheeling towards me.
I'd just recovered and I could see myself back in hospital explaining another motorcycle racing accident but I wasn't riding at the time.
i saw the bike on top of you but I couldn't help due to the fence but you kicked it off ok. At least the thether switch stayed plugged in.
Oh dear. Thats no good! Yeah I am sure it looked bad. I am just lucky I race a nice light 2 stroke. :niceone: In a bit of pain now. It seams you need a little more warm up before gymnastics. I got off light. Silly late move.
TZ350
28th December 2015, 20:29
The whole build can be seen by following the backstory posts like a trail of breadcrumbs.
... backstory posts trail of breadcrumbs.
The Dry Sump and Gear Oiler, not to sure how well this idea will work so I am going to try it on the old air cooled engine first.
317734 317736
... but the trans spins so slow compared to crank, curious as to what the actual gain is with an oil pump.
I am curious too, so it is one of the reasons I am re cycling the old air cooled motor which I have dyno data for. I will fit the old air cooled motor to the new chassis for testing before I put the super duper 110cc NSR/GP motor into the new frame.
Apart from any potential performance gain from a dry sumped motor I basically have to do it because the motor is so heavily tilted down at the front in the new frame that all the gear box oil will flood the rotary valve area and leave the gears dry, so I have to pump it back over the gears to lubricate them.
And if your pumping oil around you might as well run it through an oil cooler too. And if you have an oil cooler you might as well make it as efficient as possible with a fan to shift air through it. Anyway that was the thinking. But with Wobbly pointing out that 150ml of oil was enough for the BSL 500 I will re think how big a catch tank I need.
A bit more progress, managed to get the air cooled engine together and fitted into the NSR250 frame.
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The original plan was for a bunch of ducting to go on and the motor slanted down so as to expose the center of the cylinder head to the cooling blast of air that will be ducted in, in between the fork legs. If I can I would like to extend the ducting all the way from the front high pressure area to the low pressure area behind the bike.
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The original plan was for an air cooled engine, then the Gods smiled and I could build a 110cc water cooled engine. The six speed H2O unit is on the floor and will go in when I have tested the gear box dry sump idea with the air cooled unit.
I have to try the dry sump idea with the air cooled unit first because I have good dyno data for this air cooled motor in standard wet gearbox and clutch trim. And it would be nice to know if the dry sump idea is worth any power at the back wheel before I fit the water cooler.
Frits Overmars
28th December 2015, 20:52
Hey Frits, was this book ever published in English? I wouldn't mind another well written book on the shelf to fool my guests into thinking I'm smart.Not to my knowledge. But maybe someone pushed it through the GoogleTranslator.
Surely a technical book in a "foreign" language would impress your guests more rather than just another English language tome.I think so too. I have a lot of books in foreign languages, mainly English :whistle:
dtenney
30th December 2015, 03:30
We have been dyno testing a 125cc rotary valve motor using both carbon fiber and steel rotary valves. We are quickly seeing wear around the inlet hole. Does anyone have coating suggestions for the RV running surfaces that will minimize the wear?
Thanks,
David
teriks
30th December 2015, 03:53
We have been dyno testing a 125cc rotary valve motor using both carbon fiber and steel rotary valves. We are quickly seeing wear around the inlet hole. Does anyone have coating suggestions for the RV running surfaces that will minimize the wear?
Thanks,
David
I have dealt with some Tufram coatings at work, but not in engines, yet. I think L4 or FC12 are good candidates for that application if the rest of the part is up to anodizing. You might need too much masking if the running surface is part of the case though.
http://www.magnaplate.com/coatings/tufram
dtenney
30th December 2015, 04:27
I have dealt with some Tufram coatings at work, but not in engines, yet. I think L4 or FC12 are good candidates for that application if the rest of the part is up to anodizing. You might need too much masking if the running surface is part of the case though.
http://www.magnaplate.com/coatings/tufram
Thanks Teriks. These coatings look interesting.
DT
ief
30th December 2015, 05:58
Can't seem to find it, TZ, for the copper baseplate, did u just use some copperspray, no gaskets right? Seal ok that way and anealed first?
seattle smitty
30th December 2015, 06:01
http://www.kgcoatings.com/products/2400-series-gun-kote
Dave , take a look at post #15312, page 1021. There are some related follow-on posts, too. This is a cheap, do-it-yourself fix-up, a heat-cured dry lubricant that you apply with an air-brush (and I'm suggesting doing this to the case halves, not the disc). Zak did a lot of this moly-coating, tho' I don't know if he did rotary valve cases. Do you think the leading edge of your valve disc is flexing in and out as it passes the hole, and maybe digging into the edges of the hole? Can you give the edges just a little bit of ramp (and make sure the moly coating covers that ramp)??
Frits Overmars
30th December 2015, 06:55
Do you think the leading edge of your valve disc is flexing in and out as it passes the hole, and maybe digging into the edges of the hole? Can you give the edges just a little bit of ramp (and make sure the moly coating covers that ramp)??Don't give the edges of the hole a ramp; give the leading edge of the disc a ramp, so it will plane on the oil instead of scraping it off.
dtenney
30th December 2015, 09:39
Don't give the edges of the hole a ramp; give the leading edge of the disc a ramp, so it will plane on the oil instead of scraping it off.
Frits:
Just to make sure i understand.......I should taper the edge of the rotary valve so the oil will not get scraped away but will flow under the valve?
Thanks,
David
lodgernz
30th December 2015, 09:54
Don't give the edges of the hole a ramp; give the leading edge of the disc a ramp, so it will plane on the oil instead of scraping it off.
Both sides of the disk? Or just the crankcase side?
wobbly
30th December 2015, 11:09
Here is a pic of the best shape to prevent the disc from pulling into the port as it sweeps over it - and wearing the case.
The disc spins anticlock - so the outer leading edge of the closing side of the disc is well supported ( as its past the port hole ) and
the inner corner radius of the disc actually forms the closing timing point with the bottom left corner of the port.
Thus the port closes gradually from the outside inward, with the timing still set at the usual 140/90 numbers.
The only thing that changes is the last part of the port to be open at 90* is the bottom left corner.
We tried a huge number of shapes when dynoing at Zip the Hines 250 Superkart title winning engines and even had a full port shaped radius ( convex and concave )
on both leading and trailing edges plus combinations of straight edges and curved ie everything we could think of.
The port shape that was wider at the top, and smaller at the bottom with dead straight blade edges made the best overev power, but it wore out the dyno case in no time.
So we went back to the symmetrical shaped port as per the Aprilia pics.
Note that the later RSA port is rotated 90*, with the widest port chord on the centreline thru the crank, giving the same area as the older RSW port, but a smaller footprint of
the valves intrusion for any particular timing duration.
Having the blade not inside the port for the most time, ie with a "narrow " port angular width, gives better power for the same timings as a wide port.
Edit - added pic of later RSA port with widest chord on crank center line , also just added older RSA version.
kel
30th December 2015, 11:55
The disc spins anticlock - so the outer leading edge of the closing side of the disc is well supported ( as its past the port hole ) and
the inner corner radius of the disc actually forms the closing timing point with the bottom left corner of the port.
Are you sure? I believe (and have posted before) that the disc spins clockwise. Reason behind this is due to the best flow with partially open carburettor is achieved by opening the inlet port from the bottom up. Spin the disc anti clockwise and you have soft closing, spin it clockwise and you more or less get the port opening from the bottom up as per the RSA. And as the man says - Jan Thiel "I thought about this when we designed the RSA. And made the inlet open from the bottom!"
wobbly
30th December 2015, 12:16
When Jan first designed the RSA it had the wide port chord horizontal.
The last versions had the port turned 90* so the wide chord was vertical, and at the same time the angled blade edge was reversed
simply to stop the bad wear problems - with no power downside.
I asked Jan after Frits gave me his email, and the first question to him was why the blade change, as well as the port orientation - the answer , wear , nothing else.
With the port chord change, so did the flow regime.
The first pic I showed was an old 250 - I was just demonstrating the blade shape, not the actual spin direction of that motor.
TZ350
30th December 2015, 18:14
Looking at the pics my first reaction is to " fix " the insert - that is extend the floor all the way out to the flange face.
As I said earlier having the dam in place makes the exit area much bigger than that at the port - and we already know that the reverse scenario makes better power.
Having a much smaller area at the port may in fact work really well if the whole duct is reduced to suit, keeping the Mach number higher right down to the header.
Thanks, it is a team effort, hopefully Chambers will be happy to continue the experiment because he is the one doing all the real work making the changes.
I only help by recording the dyno runs and posting the results. I am looking forward to adding to the Team ESE stable by completing my own 50 with the information we find out from Chambers efforts.
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Radius edge on the exhaust port dam
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Red = radius on the leading edge of the exhaust port dam, Blue = sharp edge.
Radius is better.
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Red = radius edged dam, Blue = No Dam.
Above is the back story so far.
Now, tonight we had more dyno adventures with Chambers RG50.
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Blue = best with no dam, Red = original dam with radiused edge level with TPO , Green = radiused dam opening 4 deg after TPO.
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Blue = Exhaust dam level with TPO. Red = Dam opening 4 deg after TPO.
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Engmod warned us that razing the port timing would not work, it was right. Red = barrel raised 0.5mm or one base gasket.
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Where we are now, Blue = best with no dam, Red best of where we are now at with an exhaust dam.
We are getting there, Chambers now has the dam making a touch more maximum power than the no dam version.
Next move is to start opening up the "A" transfer ports and pointing them more towards the center of the cylinder for more power by taking advantage of the short circuiting blocking powers of the exhaust dam.
Here is hoping.
F5 Dave
30th December 2015, 18:56
Hmm. So why the dramatic increase of peak power? Temperature fooling the pipe?
Frits Overmars
30th December 2015, 19:32
Frits: Just to make sure i understand.......I should taper the edge of the rotary valve so the oil will not get scraped away but will flow under the valve?You got it David. You want the disc to go aqua-planing. or in this case: oil-planing.
Both sides of the disk? Or just the crankcase side?Both sides. But why would you give preference to the crankcase side? Usually the outer disc cover suffers most from wear. In theory you don't even need the inner surface.
If the disc eats into the crankcase side, it means the flow is still pushing the disc inward when the port closes. In other words: the disc closes too early.
Or, and this is a big or, the inlet tract is too long, causing a big amount of inertia in the inlet flow; it will be reluctant to start flowing and just as reluctant to stop.
Shortening the complete tract may solve the wear problem and boost the power as well.
TZ350
30th December 2015, 19:45
Hmm. So why the dramatic increase of peak power? Temperature fooling the pipe?
Not sure, it could be that the blowdown is improved with the dam and allowing a higher rpm ceiling. With the first "Exhaust Dam" tests we tried different main jets but over a wide-ish range there was not much difference. So we tried to keep everything consistent by not changing the ignition timing or main jets etc, we just ran the same setup. The piston is showing a bit of real heat in the crown. Not to sure whats up with that but I am very interested to see what happens when the "A" transfers get re angled across the piston crown.
Frits Overmars
30th December 2015, 19:46
Next move is to start opening up the "A" transfer ports and pointing them more towards the center of the cylinder for more power by taking advantage of the short circuiting blocking powers of the exhaust dam. Tread very carefully here; don't try it with your best cylinder.
TZ350
30th December 2015, 20:09
Tread very carefully here; don't try it with your best cylinder.
We would love it to be a stunning success but know it is a bit way out there, so we are sort of emotionally prepared for final tragedy, and count on having picked up some useful gems along the way.
wobbly
30th December 2015, 20:50
But I feel I must add here, that my whole perception of dyno testing was changed by Jan stating that alot of the pipe testing that was originally done
was invalidated in that the jetting wasn't optimised for each change of dimensions.
What he was saying is that if a pipe affected the egt due to its design, then the power change was due to the egt change - not the actual efficiency ( or not ) of the actual pipe.
I have taken this on board and for some time EVERY run I do I aim to jet for exactly the same peak power egt.
A small change in reed stiffness will absolutely change the egt number, and if you dont then rejet to achieve the target, then the temp change is causing the power difference - not the reed change.
I shoot for 650*C on a KZ2 for example as this is what we see for best power.
Now I am starting to use Lambda, to achieve a target A/F ratio.
Both methods, are in effect approximating what should really be done to do this properly, that is measuring air and fuel flow to generate a max power BSFC number.
But anyway, what I am saying is that just doing a dyno run, making a change and then not rejetting - is a waste of effort.
TZ350
31st December 2015, 05:24
And here we were thinking we were doing it properly by changing only one thing, :doh:
I will talk with chambers about getting some good EGT gear. ... :D
dtenney
31st December 2015, 05:38
sent you a PM....pls confirm it went through.
F5 Dave
31st December 2015, 07:18
Hmm. So why the dramatic increase of peak power? Temperature fooling the pipe?
TZ, I badly worded my post.
I meant to say dramatic increase of revs at peak power.
Its like you've chopped an inch out of the pipe. Either the jetting requirement is different, or the dam is well overheating locally and you might not see the benefit if you cool it with more petrol as if it were cast in. Maybe, just something to consider.
41juergen
31st December 2015, 07:41
But I feel I must add here, that my whole perception of dyno testing was changed by Jan stating that alot of the pipe testing that was originally done
was invalidated in that the jetting wasn't optimised for each change of dimensions.
What he was saying is that if a pipe affected the egt due to its design, then the power change was due to the egt change - not the actual efficiency ( or not ) of the actual pipe.
I have taken this on board and for some time EVERY run I do I aim to jet for exactly the same peak power egt.
A small change in reed stiffness will absolutely change the egt number, and if you dont then rejet to achieve the target, then the temp change is causing the power difference - not the reed change.
I shoot for 650*C on a KZ2 for example as this is what we see for best power.
Now I am starting to use Lambda, to achieve a target A/F ratio.
Both methods, are in effect approximating what should really be done to do this properly, that is measuring air and fuel flow to generate a max power BSFC number.
But anyway, what I am saying is that just doing a dyno run, making a change and then not rejetting - is a waste of effort.
Hey Wob, what type of lambda sensor do you use (I assume wide band sensor, right)? Do you just take the millivolt signal or do you have a controller taking care on the heating and the signal conversion? I had an ETAS system in the beginning, now using the WBO2 setup...
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gamma500
31st December 2015, 08:40
Maybe we will soon know whats inside the ryger engine...
wobbly
31st December 2015, 09:36
Hi David, yes I got the PM with your home address, but not an email.
The Lambda I use is from Innovate Motorsports with a Bosch heated wideband, and it can read out in various formats.
It will convert directly to A/F ratio, Lambda Number, or 0-5V, I use the A/F ratio as an input direct to the dyno datalogger so as to see
the power overlayed with A/F as well as deto etc.
The probe is in the front of the muffler,with a threaded insert that sits right on top of the perf tube.
It has a gauge reading out A/F, but you for sure havnt time to watch that when doing a dyno run.
One take on the dam idea affecting the top end so much, is that is exactly the effect you see by putting a 75% nozzle in the duct exit when running a sim.
This is why I thought the next step should be to extend the floor right out the flange face.
Gaining all that top end means you have an option to redesign the pipe for better mid, or use the overev capability and use the pipe to make even more power up top.
The Ryger homologation is due to be published publicly by the CIK on the 1st Jan.
I will be onto the site all day looking for the info we all are screaming for.
speedpro
31st December 2015, 09:53
This is what I use: http://www.ecotrons.com/products/wideband-controller-alm-gauge/
The controller output is configurable and you can connect an injector input to it for rev information. Supplied with software to monitor, record, and control. I have mine setup just to monitor the lambda with the gauge but another output is being fed to the ECU and the Lambda is recorded along with other ECU parameters during engine operation. Hopefully today I will start(again) with autotuning using the lambda output to the ECU and a brake dyno type of thing to hold certain revs and load. Cool little feature where the system automatically tunes itself for lambda=1, or with the flick of a switch it tunes to a "desired" lambda in another table with a range of values over various loads, throttle positions, and revs
speedpro
31st December 2015, 10:10
Just had another look and saw this: http://www.ecotrons.com/products/alm-diesel/
Might be more resilient in the 2-stroke environment, if that's a problem.
Yow Ling
31st December 2015, 11:51
Frits posted this in Foundry Thread
318339
Looks a bit like a copy of Flettners crank
https://youtu.be/-2AhNvDFNlQ
"Linear rod crank, no cams, no scotch yoke, just a crank within a crank. Each crank offset is 12.5mm, total stroke is 50mm. Not over hung, fully supported. Clicking sound is the rod touching the case at the bottom, will sort that next time it's apart. TF 100 case
So if somewhat different than the Ryger we also can have a oil less top end with HCCI that could technically rev to approx 30,000 rpm."
TZ350
31st December 2015, 16:42
Hmm. So why the dramatic increase of peak power? Temperature fooling the pipe?
TZ, I badly worded my post.
I meant to say dramatic increase of revs at peak power.
Its like you've chopped an inch out of the pipe. Either the jetting requirement is different, or the dam is well overheating locally and you might not see the benefit if you cool it with more petrol as if it were cast in. Maybe, just something to consider.
I now think it is the sort of lean heat rpm you see when turning the PJ off. Not sure it is a good thing in this case, anyway those extra rpm disappeared when we jetted up so I think your suspicions may be right.
TZ350
31st December 2015, 16:51
The back story so far.
318266
Where we are now, Blue = best with no dam, Red best of where we are now at with an exhaust dam.
Next move is to start opening up the "A" transfer ports and pointing them more towards the center of the cylinder for more power by taking advantage of the short circuiting blocking powers of the exhaust dam. Here is hoping.
318344
Chambers widened up the "A" ports, did a good job considering our clumsy tools he had to work with. Kel brought around his dinky little right angle air grinder, it is great for 50mm 100cc bores but sadly too big for the 41mm 50 cylinder.
318346
Exhaust port dam ... Blue = Standard "A" ports, Red = Widened "A" ports. Useful improvement in bottom end power.
318345
Green is the best we have managed without the Exhaust port dam, so still some work to do yet.
Frits Overmars
31st December 2015, 20:06
Frits posted this in Foundry Thread
318339
[/QUOTE]So you can be sure it's not the Ryger crank, Yow Ling. If it were, I would not yet be allowed to post it.
Exhaust port dam ... Blue = Standard "A" ports, Red = Widened "A" ports. Useful improvement in bottom end power.That is what you can expect when short-circuiting from the A-ports into the exhaust lowers the EGT, Rob.
TZ350
31st December 2015, 21:39
That is what you can expect when short-circuiting from the A-ports into the exhaust lowers the EGT, Rob.
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Hi Frits, are you saying that, that lower improvement in the Red line is more likely due to short-circuiting and not better trapping by the Dam? I thought we were doing well, but could it be, we have to re visit the "A" port angles.
breezy
31st December 2015, 23:45
TZ350, do you think that short circuiting will always occur from somewhere to some extent? and the dam in the exhaust has changed from where the short circuiting is now occurring. Looks like the dam is really upsetting all the other parameters?/ scavenging pattern?:weep::weep:
peewee
1st January 2016, 07:48
Hi David, yes I got the PM with your home address, but not an email.
The Lambda I use is from Innovate Motorsports with a Bosch heated wideband, and it can read out in various formats.
It will convert directly to A/F ratio, Lambda Number, or 0-5V, I use the A/F ratio as an input direct to the dyno datalogger so as to see
the power overlayed with A/F as well as deto etc.
The probe is in the front of the muffler,with a threaded insert that sits right on top of the perf tube.
It has a gauge reading out A/F, but you for sure havnt time to watch that when doing a dyno run.
One take on the dam idea affecting the top end so much, is that is exactly the effect you see by putting a 75% nozzle in the duct exit when running a sim.
This is why I thought the next step should be to extend the floor right out the flange face.
Gaining all that top end means you have an option to redesign the pipe for better mid, or use the overev capability and use the pipe to make even more power up top.
The Ryger homologation is due to be published publicly by the CIK on the 1st Jan.
I will be onto the site all day looking for the info we all are screaming for.
is this one you use ? http://www.lectronfuelsystems.com/products/wego_III_O2_sensor_kit.html
TZ350
1st January 2016, 08:07
TZ350, do you think that short circuiting will always occur from somewhere to some extent? and the dam in the exhaust has changed from where the short circuiting is now occurring. Looks like the dam is really upsetting all the other parameters?/ scavenging pattern?:weep::weep:
Yes, the dam has not been an instant success, still not finished with it yet. We have better (13.5hp) 50's but want to explore the dam idea a bit further.
Our porting tools are pretty clumsy and not at all suited for 50's so the ports could be better shaped. We might have to bite the bullet and upgrade our tooling.
Also we have not got as far as trying Wobblys suggestion of checking the Mac numbers in Engmod (requires some learning on my part) and extending the dam further in the exhaust duct to keep up the gas velocity. That will require a completely new dam which is a bit of hard work to make.
TZ350
1st January 2016, 08:20
That is what you can expect when short-circuiting from the A-ports into the exhaust lowers the EGT, Rob.
Hi Frits, Chambers did comment that it was not running as hot, at the time I thought it was a good thing. .... lots to think about....
TZ350
1st January 2016, 09:17
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These are the basic hand porting tools we have to work with. Chambers has done pretty well with them but they are just to clumsy for 50cc engines.
318360
This basic approach to porting unlocked good power from the Suzuki GP engines. We were hoping for something similar from the exhaust port dam idea, big results from a simple approach.
breezy
1st January 2016, 09:43
Yes, the dam has not been an instant success, still not finished with it yet. We have better (13.5hp) 50's but want to explore the dam idea a bit further.
Our porting tools are pretty clumsy and not at all suited for 50's so the ports could be better shaped. We might have to bite the bullet and upgrade our tooling.
Also we have not got as far as trying Wobblys suggestion of checking the Mac numbers in Engmod (requires some learning on my part) and extending the dam further in the exhaust duct to keep up the gas velocity. That will require a completely new dam which is a bit of hard work to make.
i think Luc Foekema may be able to point you in the right direction without the raising the exhaust port floor. ask him, seems to be a nice bloke(facebook):sherlock:
wobbly
1st January 2016, 09:43
Thats what I alluded to re tracking EGT with a really fast response probe ( open tip, Stinger from EGT Industries - guaranteed for 2 years ) and datalogging it against power.
If the egt has dropped from say 650 to 600, then it would need at least 2 jets leaner to get back to your baseline.
2 jets is night and day power wise, and peak power rpm wise.
And as you well know, if the mid has gone rich in relation to the top,then you will need to adjust the air correction to skew the fuel curve as well.
This is the controller I use for the Lambda,and this sends the A/F corrected numbers to the dyno datalogger - 12.8:1 makes alot more sense to me than 0.9 Lambda ever did.
http://www.innovatemotorsports.com/products/lc2.php
karter444
1st January 2016, 10:06
318344
Chambers widened up the "A" ports, did a good job considering our clumsy tools he had to work with. Kel brought around his dinky little right angle air grinder, it is great for 50mm 100cc bores but sadly too big for the 41mm 50 cylinder.
318346
Exhaust port dam ... Blue = Standard "A" ports, Red = Widened "A" ports. Useful improvement in bottom end power.
318345
Green is the best we have managed without the Exhaust port dam, so still some work to do yet.
two easy things that you could try
maybe grind a large angle on the duct side of the dam , this may help the returning air fuel mixture being forced back into the cylinder by the action of the pipe
maybe grind the centre out of the dam , turn it into a V shape , it may help with flow in and out of the port , but still replicate large lower port radius
cheers
TZ350
1st January 2016, 10:46
two easy things that you could try, maybe grind a large angle on the duct side of the dam , this may help the returning air fuel mixture being forced back into the cylinder by the action of the pipe.
We have that now. Wob suggests extending it out to the end of the duct to keep the gas velocity up. He also suggests I model the exhaust duct carefully in EngMod and look at the pressure wave in the exhaust duct to see if its suffering sonic choking. I intend doing that but it requires me to take the time to up skill my abilities with Engmod a bit first.
318363
maybe grind the centre out of the dam , turn it into a V shape , it may help with flow in and out of the port , but still replicate large lower port radius
cheers
Yes good idea, we will try it maybe after cleaning up the A port.
TZ350
1st January 2016, 10:56
I think Luc Foekema may be able to point you in the right direction without the raising the exhaust port floor. ask him, seems to be a nice bloke(facebook):sherlock:
Ok, I now have got a facebook page thingy, (thanks to 11 year old grandson) even been accepted as a friend by Luc but I have not quite mastered Facebook well enough to use it very successfully, just need a bit of practice with it I guess.
kel
1st January 2016, 11:07
Looks like the dam is really upsetting all the other parameters?/ scavenging pattern?:weep::weep:
I was wondering about this myself. The hooks in the B ports force flow under the bulk incoming scavenge charge to help expel the previous cycles residual burnt charge, the raised exhaust port floor maybe impacting on this.
https://www.youtube.com/watch?v=3F_0PvbKo44
Maybe you could try lowering the centre of the port some, along the lines of the RSA exhaust port shape,
318364
and radius the lower edge?
TZ350
1st January 2016, 11:19
263028
Ok mine turned up today.
263027
And a couple of two wire sensors I picked up cheap from the local garage.
There has been some questions about a knock gauge sensors and detection module. The module that I use came from:- http://www.knockgauge.eu/ there is more information in the links list on page 1410
TZ350
1st January 2016, 11:25
Looks like the dam is really upsetting all the other parameters?/ scavenging pattern!!
I was wondering about this myself. The hooks in the B ports force flow under the bulk incoming scavenge charge to help expel the previous cycles residual burnt charge, the raised exhaust port floor maybe impacting on this.
Maybe you could try lowering the centre of the port some, along the lines of the RSA exhaust port shape,
318367
and radius the lower edge?
318365
The narrow part of the exhaust window is the original RG50 port and the wider part above the dam is 85% of the bore width.
Without the dam we could have something that looks like the RSA exhaust port.
AndreasL
1st January 2016, 12:39
Ok, it's 2016.
Ryger please. ;)
TZ350
1st January 2016, 14:47
318368318372
Ok started on learning how to model a profiled exhaust in Engmod2T. Until we get the cylinder off again I can only guess at the real dimensions but my first effort more or less looks like the real thing.
318373
Ran the simulation and generated data for the plot options.
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In the Post 2t plot options for Thermo and Gas dynamics there is a choice for "Ex mach(1)", "Ex mach(2)" and "Ex machout". The help file does not explain what these are so I guessed that "Ex mach(1)" was the mach number at the exhaust port window, I have no idea what the other two are. In fact it looks like I have lost the entire help file, not sure why.
318369
Mach numbers at two rpm points. I am not sure how to interpret these but I guess they are both choked for a bit after the exhaust port opens.
Some guidance by anyone who is familiar with Engmod about what the traces mean would be great.
TZ350
1st January 2016, 14:56
Looking at the pics my first reaction is to " fix " the insert - that is extend the floor all the way out to the flange face.
As I said earlier having the dam in place makes the exit area much bigger than that at the port - and we already know that the reverse scenario makes better power.
Having a much smaller area at the port may in fact work really well if the whole duct is reduced to suit, keeping the Mach number higher right down to the header.
TeeZee, try putting the measured data into EngMod and have a look at the Mach, down the duct length by varying the position of the Ex sensor.
Test it as it is now, then make the exit area much smaller as well - the power thrown up will be an indication of the result,but the Mach number gives us some insight into the actual effect.
In this case, maybe having a much smaller duct vol, with steps, like an old RS125, at the header, just might be a nice Xmas prezzy.
To make the sim really accurate, you will need to specify an actual step in the pipe input, as this has a big affect on the in and outflow calculations.
Found Wobs post on using Engmod to look at the mach numbers.
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I would love some guidance on what the graph means.
TZ350
1st January 2016, 21:16
318417
While I was trying to figure out what I had done to the help files I became distracted by this very interesting read on how to use Engmod's Post 2T program to investigate the cause of detonation in your simulation and how to design a solution.
AndreasL
1st January 2016, 22:13
I would love some guidance on what the graph means.
I had the same questions some pages ago that Wobbly gave some answers to.
Hope that help some.
TZ350
1st January 2016, 22:29
I had the same questions some pages ago that Wobbly gave some answers to.
Ok found it, thanks. Now to digest it.
wobbly, a EngMod question if you don't mind...
When designing a exhaust duct using EngMod, I think it's ExMach that should be used to check if we go sonic or not?
ExPMach, measured at the port(?), goes through the roof (>3) when the port opens so that can't be the right thing to use...
So what I'm planing is to reduce my exduct end area until we are about to kiss sonic. Can it be that simple really? Probably not...
Using ExMach, do we like to place our virtual transducer at the smallest cross section area of the duct, i.e. just before the header (if not using some sort of adapter/spigot that is). Normally I run it at 0mm but that might not be the best thing in this case?
I'm running some rough sims right now and we are getting closer to sonic when makin the duct area smaller...as expected. But with a single port, we might push it to far using this crude "technique"...
Do you have a graph from "a decent engine" showing what to look for regarding exhaust duct speed?
Here is a KTM250 for road racing I have worked on. This is not anywhere near "full noise " as it needs powerband width to cope with a 1500 rpm drop into 5th gear.
The Ex port at the face goes well sonic as the piston opens and closes - so the lifted floor has nothing to do with flow velocity, its all to do with A port short circuiting.
I am going to try a big radius on just the floor of a lifted port to see if it raises power by increasing the outflow Cd, without affecting the short circuit reduction down the sides where the corner rads are.
The transducer is set at the smallest area in the duct ( the cylinder face ) before the oval/round transition spigot, and this gave the best power - going smaller did not gain any power.
Going bigger did loose immediately, and it seems that in many engines going to around 0.8Mach at the exit seems to work best..
The stinger venturi just goes sonic for a short period, but again, this was the smallest area for best overall power without deto.
I could go bigger, and then i would need to add timing or increase com to compensate to lift the TuB number- and this lost band width.
As I have stated a hundred times the 75% area at the oval face will get you close every time, as will the 90% area for a single port.
Just remember that the sim will reduce the volume of the duct in a linear fashion, as you neck down the exit area, and this is the correct approach - not just weld up the last 20mm
as its easy to get at.
Also the sim has no idea there is a wall in front of the piston at BDC if you lift the port floor.
It cannot therefore adjust for any improved scavenging or trapping efficiency due to reducing the A port short circuiting - all its doing is reflecting the affect on in and outflow from a smaller port/duct exit.
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TZ Keep in mind that my take on this is that the major effect is upon the A port short circuiting factor. If you look at ducts that have had the floor lifted alot the bulk flow goes sonic quite severely, and this I feel can override the positive effect of the A port trapping efficiency.
Try lowering the floor but leave as much infill in the bottom corners as you can. And at some stage try the big radius on the floor port corner only, as this will increase the outflow Cd but wont influence the trapping efficiency of the corners on the bad A port flow turning. The Aprilia ducts were CNC cut.
Another issue is that the added in dam has a crap heat transfer coefficient, and thus will be overheating the retained charge in the duct.
Frits Overmars
2nd January 2016, 03:10
Hi Frits, are you saying that, that lower improvement in the Red line is more likely due to short-circuiting and not better trapping by the Dam? I thought we were doing well, but could it be, we have to re visit the "A" port angles.No, I'm not saying that; I have no way of knowing. I just wanted to point out that it might be a factor to consider.
Our porting tools are pretty clumsy and not at all suited for 50's so the ports could be better shaped. We might have to bite the bullet and upgrade our tooling. All you need for an unbridged exhaust duct is a round file.
we have not got as far as trying Wobblys suggestion of ... extending the dam further in the exhaust duct to keep up the gas velocity.From what I could see on your pictures that was the first thought that crossed my mind. Looking in from the outside the dam looked more like a brick wall than a flow-aiding insert to me.
Hi Frits, Chambers did comment that it was not running as hot, at the time I thought it was a good thing. .... lots to think about....Not running as hot should be a good thing, no doubt about it. It just depends on the reason why. Short-circuiting may aid in cooling the piston at the cost of some power.
Improved exhaust outflow may make the blowdown phase more effective, resulting in less spent gases entering the transfer ducts. and this would result in a lower cylinder temperature. Very desirable unless you want to retain a certain amount of exhaust gas in the cylinder in the interest of HCCI combustion.
The mechanical simplicity of a two-stroke can be quite deceptive...
https://www.youtube.com/watch?v=3F_0PvbKo44You should be aware that this video probably shows a quite good CFD-generated impression of a rather poor scavenging system.
TZ350
2nd January 2016, 05:44
Thanks Frits. ....
breezy
2nd January 2016, 06:26
318417
While I was trying to figure out what I had done to the help files I became distracted by this very interesting read on how to use Engmod's Post 2T program to investigate the cause of detonation in your simulation and how to design a solution.
i like this, enables a good understanding, easily,pictures and explanations, of the processes going on and the effects of each element..good post:sherlock:
peewee
2nd January 2016, 14:50
318368318372
Ok started on learning how to model a profiled exhaust in Engmod2T. Until we get the cylinder off again I can only guess at the real dimensions but my first effort more or less looks like the real thing.
318373
Ran the simulation and generated data for the plot options.
318370318371
In the Post 2t plot options for Thermo and Gas dynamics there is a choice for "Ex mach(1)", "Ex mach(2)" and "Ex machout". The help file does not explain what these are so I guessed that "Ex mach(1)" was the mach number at the exhaust port window, I have no idea what the other two are. In fact it looks like I have lost the entire help file, not sure why.
318369
Mach numbers at two rpm points. I am not sure how to interpret these but I guess they are both choked for a bit after the exhaust port opens.
Some guidance by anyone who is familiar with Engmod about what the traces mean would be great.
this was mine. it matches the cylinder fairly well but engmod doesnt have enough detail options to get the window exact. i dont have the big round corners on the aux but its the closest i could get. im a dummy with all the tracer stuff so ill be following your posts
wobbly
2nd January 2016, 14:55
The Ex Mach thing is easy to understand and use.
Once you are into the gas dynamics screen and chose Mach and your project rpm, then the graphical options are
ExPMach - this is the mach number at the port face.
ExMach1 - this is the mach at the sensor position you chose in the Engine screen - in this case we want to look at the Mach usually at the
duct exit, where the nozzle area is smallest.
ExMach2 - this is the mach in pipe 2 = the stinger in a normal single cylinder sim setup.
As the piston starts to open the port we have maximum pressure delta and the smallest area, so the initial flow goes sonic in the ExPMach trace.
Then the mach reduces as the area increases and the pressure drops - followed by an increase in flow due to the depression at the port created by the diffuser, this is then followed by the rear cone
pressure rise reversing the flow.
At the smallest area of the nozzle ( if one is correctly designed ) the Mach number will approach 0.8.
I have found that higher or lower affects the power.
Then we have the flow regime in the stinger, and again the best scenario seems to involve a short period of choked sonic flow, followed by a longer period closer to/below Mach 1.
wobbly
2nd January 2016, 15:02
Sorry double post - please remove.
TZ350
2nd January 2016, 15:05
ExPMach - this is the mach number at the port face.
ExMach1 - this is the mach at the sensor position you chose in the Engine screen - in this case we want to look at the Mach usually at the duct exit, where the nozzle area is smallest.
ExMach2 - this is the mach in pipe 2 = the stinger in a normal single cylinder sim setup.
Thanks Wob.
Also Neels has sent updates today and some info from the help file on Mach numbers.
In the Help file I was able to drill down through the index but was unable to open the related help document. As I have not needed the Help file for a while I am not sure when it stopped working properly for me. I probably inadvertently killed it when I was doing a re organization of the files.
Here is a PDF of the section of the Help file related to Mach numbers Neels sent me today.
318460
Many thanks to Neels who goes to a lot of trouble supporting the EngMod2T program.
husaberg
2nd January 2016, 15:06
Sorry double post - please remove.
You can do it yourself Wayne?
click edit post, then delete at the bottom left hand corner, then delete again.
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=309285&d=1424570781
http://www.kiwibiker.co.nz/forums/album.php?albumid=4916&attachmentid=309285
This post will auto delete in 23 hours.
https://youtu.be/MA2KmJMKFrQ?t=41s
TZ350
2nd January 2016, 19:05
The Ex Mach thing is easy to understand and use. Once you are into the gas dynamics screen and chose Mach and your project rpm, then the graphical options are
ExPMach - this is the mach number at the port face.
ExMach1 - this is the mach at the sensor position you chose in the Engine screen - in this case we want to look at the Mach usually at the duct exit, where the nozzle area is smallest.
ExMach2 - this is the mach in pipe 2 = the stinger in a normal single cylinder sim setup.
As the piston starts to open the port we have maximum pressure delta and the smallest area, so the initial flow goes sonic in the ExPMach trace.
Then the mach reduces as the area increases and the pressure drops - followed by an increase in flow due to the depression at the port created by the diffuser, this is then followed by the rear cone pressure rise reversing the flow.
At the smallest area of the nozzle ( if one is correctly designed ) the Mach number will approach 0.8. I have found that higher or lower affects the power.
Then we have the flow regime in the stinger, and again the best scenario seems to involve a short period of choked sonic flow, followed by a longer period closer to/below Mach 1.
EngMod2T simulation and engine performance analysis.
Hi Wob, I think I am getting this right, any pointers would be welcome.
318466
Max torque at 12,000 rpm.
ExMach1 - this is the mach at the sensor position you chose in the Engine screen - in this case we want to look at the Mach usually at the duct exit, where the nozzle area is smallest.
318465318468
Ok this is my Engine screen and Exhaust Port screen with 80% Exhaust port width and 90% equivalent exhaust duct diameter at the flange face. The exhaust duct is 40mm long from port window to flange face.
318467
ExMach1 Not quite 0.8 at max torque.
ExMach1 - At the smallest area of the nozzle ( if one is correctly designed ) the Mach number will approach 0.8. I have found that higher or lower affects the power.
318464
TUBmax (squish band end gas temperature) is highest at 11,000rpm. So there is untapped potential somewhere, I need to find it as TUBmax indicates that it could tolerate being higher at 12,000 plus rpm, but not to sure how to do that.
F5 Dave
2nd January 2016, 19:29
Rob, the thing is there are fundamental differences between where you are now and where you wish to one day be. Surely you will learn more modelled closer to what you have now and then see the changes. . . . . Says he who has never played with anything more sophisticated than TSR stuff of the 90s. But you have peak power set to 15500. You're around 13 in real life. Also bmep is clearly a lot lower.
What I am impressed with is that the piston hasn't escaped down the duct. Keep that skirt nice and tight to the bore.
TZ350
2nd January 2016, 19:51
you have peak power set to 15500. You're around 13 in real life
318472
Yes, good spotting, I forgot to set it back to 13. I was playing with it to see what the piston speed would be. At 15,000 rpm it is only just touching the performance range. At 13 it is below industrial, God knows what rpm is required to get an RG50's piston speed into the high performance range 22,000+rpm maybe.
318471
BMEP sets a target for the port STA's so you can compare where your at with where you want to be, funnily enough you can often exceed the required STA on some port and then that is another sort of clue.
What I am impressed with is that the piston hasn't escaped down the duct. Keep that skirt nice and tight to the bore.
Yes it is a bit wild, but now I am trying to bring some science to the party by using EngMod to work out the best exhaust port duct area for an 80% single Exhaust port window. Not finished yet but it looks to be about 22.75mm at the flange face. But what we do know for sure is that the standard RG50 or RMX50 exhaust duct is way to big at 26mm. Who would have thought that.
F5 Dave
2nd January 2016, 21:02
Thought something else was odd. Stroke std is 37.8 not 37.5. My memory isn't what it used to be but I can still catch the odd (irrelevant) thing.
Perhaps try one of those KTM pistons(never measured one) , the Suzuki ones with the thick rings will be slinging away power as you rev then to heck despite the lower piston speed.
TZ350
2nd January 2016, 21:54
Stroke std is 37.8 not 37.5.
Thanks for that.
Perhaps try one of those KTM pistons(never measured one) , the Suzuki ones with the thick rings will be slinging away power as you rev then to heck despite the lower piston speed.
I think KTM is to big, may be wrong. I have some 41mm Barrakit pistons with 1mm thick rings. I was truly surprised by how low the piston speed is in a RG50.
husaberg
2nd January 2016, 21:58
Thanks for that.
I think KTM is to big, may be wrong. I have some 41mm Barrakit pistons with 1mm thick rings. I was truly surprised by how low the piston speed is in a RG50.
39.5mm on the Katie
TZ350
2nd January 2016, 22:00
39.5mm on the Katie
Ok to small, a lot of 50 pistons are. I must have been thinking of the KTM65 maybe.
husaberg
2nd January 2016, 22:04
Ok to small, a lot of 50 pistons are. I must have been thinking of the KTM65 maybe.
The stoke is pretty much the same. I are meaning the KTM50's and 60'S within a smige.. the KTM 60 cylinder fits on the KTM50 on the Beta engines (up to 1998) not sure if the later 50-65 works or not but judging by the cylinder (the 50 looks like it was designed as a 65)
There is a KTM60cc (up to about 1998) version as well plus an overbore 50/60 that likely uses the KTM60 piston the there is an over bore for the 60-85cc kit plus the factory 85-105cc which is a 52mm piston with a 14mm pin.
plus there is other earlier versions and other 50CC MX engines
teriks
2nd January 2016, 23:53
In the Help file I was able to drill down through the index but was unable to open the related help document. As I have not needed the Help file for a while I am not sure when it stopped working properly for me. I probably inadvertently killed it when I was doing a re organization of the files.
I don't think you did anything wrong with the file shuffling, it's a single file, so if you can open the help at all, the topics should be there.
I did run into a similar issue though when reading the updated Dat2T help file.
The "+" on each topic disappeared making it impossible to expand the sections, that is until I found the scroll bar at the bottom of the navigation pane.
318477
Just move that thing marked yellow around and I bet you'll find your topics again. :)
Many thanks to Neels who goes to a lot of trouble supporting the EngMod2T program.
Agreed!
AndreasL
3rd January 2016, 01:52
Maybe obvious to all others, but you did your measures at max torque TZ.
I have just played around a small bit with the mach numbers...at peek power...
I guess both can be interesting to analyze, but is one "more right" then the other?
Great summary of this feature and big thanks to Neels as well!
Lef16
3rd January 2016, 03:16
Hey guys,
any news on ryger engine?
Cheers
Martin1981
3rd January 2016, 03:41
Hey guys,
any news on ryger engine?
Cheers
No. If there were any News they would have been posted already. Without anybody asking for it. Happy New Year!
peewee
3rd January 2016, 05:51
hey wob I see a lot of rods have the rib in the center from the manufacture process. do you bother polishing it down ? so far ive never had a failure and never polished them down but none of my engine have extreme power. if they were polished wouldn't that remove any shotpeening from the surface ? whats the inside scoop on this
TZ350
3rd January 2016, 05:55
Maybe obvious to all others, but you did your measures at max torque TZ.I have just played around a small bit with the mach numbers...at peak power...
I guess both can be interesting to analyze, but is one "more right" than the other?
Peak Torque or Peak Power, I chose peak torque because that is where everything is working at its best and I wanted to keep it simple by displaying only one trace.
But in fact the Wave and Mach action can be investigated at any rpm point in the search for improvements.
318481 318482
Here is a trace overlay of Mach numbers for 10-11-12-13K rpm taken at the flange face 40mm down the exhaust duct. It is interesting to compare them to the torque curve.
TZ350
3rd January 2016, 05:58
318477
Just move that thing marked yellow around and I bet you'll find your topics again. :)
Thanks, I will try that.
...... nope, that did not work for me.
TZ350
3rd January 2016, 08:19
318484318483
This is a model of the exhaust port dam.
318485318486
The aluminium insert is not quite as good as the model but good enough to test on the dyno.
The RG50's exhaust duct diameter is 26mm at the flange face and because EngMod is pointing to 23mm as being more ideal we might try an entirely different approach to the exhaust dam idea that incorporates Wobblys suggestion of using the insert to reduce the duct area at the flange face. Maybe make something out of copper that is pressed into the exhaust duct for better heat transfer to the water jacket.
wobbly
3rd January 2016, 09:06
TeeZee, the Mach numbers are telling you exactly what you need to know.
The port layout as it stands with the huge width above the transfers is operating like a T or 3 port, thus the Mach numbers for ExMach 1 are too low
as I have found most ducts taken down to 75% area at the flange will approach 0.8Mach - and this seems to be the best compromise for power.
The TuB number that is very high down low like yours is usually easily fixed by pulling out some timing, and then the whole curve can be lifted by making the stinger smaller, or cranking in more timing.
You can juggle com/timing/stinger in endless combinations, but the number will always drop away toward peak power as the timing needs to be pulled to get more heat into the pipe.
This is always more effective than using most of the finite combustion energy to compress the gas, as a longer pipe can be used with less timing - and this makes more overall power.
But sometimes this effect of a high TuB down low is caused by the reeds being very effective, due to their first harmonic tuning being in that range - have a look at that.
The Ex outlet being too big on every engine is exactly what I found years ago when I first started seriously using EngMod, and this developed into my 75% area rule of thumb soon after
that Neels has now incorporated into the inputs screens.
Re polishing the beams on rods.
When you do this you are cutting thru the highly compressed skin created by the forging process.
The as forged skin may look like shit, but is in fact very strong.
Polishing removes all the small imperfections and stress raisers, but then the rod MUST be re shot peined.
The finished result will be much stronger again than the original as forged item, and lighter.
TZ350
3rd January 2016, 09:48
Thanks Wob, now I know a bit more about using Engmod effectively I will use it and your comments to develop a plan for the next step in tuning the RG50.
ief
3rd January 2016, 10:10
would some form of aluweld be more effective in shaping the duct? Comes in different temp variations and sticks to most metal.
Just don't know if it will cope with the temps but guess it will (?)
husaberg
3rd January 2016, 10:17
Re polishing the beams on rods.
When you do this you are cutting thru the highly compressed skin created by the forging process.
The as forged skin may look like shit, but is in fact very strong.
Polishing removes all the small imperfections and stress raisers, but then the rod MUST be re shot peined.
The finished result will be much stronger again than the original as forged item, and lighter.
The easiest way to do this is with linisher its surprising quick, so be careful, I recommend practising on a old rod first.( I learnt that the hard way:laugh:)
The Air NZ workshop in CHCH used to do the peening (for beer money) as well as dynamically balancing the old Brit twin cranks for a lot of people not sure if it even still exists to this level anymore now likely a lot of stuff is outsourced.
The peening appears to give it a finish that resists minor corrosion not sure why.
wobbly
3rd January 2016, 10:18
One more small detail is the length of the duct to where you form the smallest area nozzle.
In my experience one bore diameter is too short for the duct length - including the spigot/venturi.
Closer to 2* bore seems to be better.
So in the case of the RG50 it is easy enough to fabricate a longer bolt on spigot after you have had a play in Engmod by lengthening the duct and shortening the pipe.
The KTM one shown was a female spigot with the duct at 1* the bore, it worked way better and was easyer to transition better closer to 2* with an insert that became
a male slip joint.
TZ350
3rd January 2016, 11:15
318490
One more small detail is the length of the duct to where you form the smallest area nozzle. In my experience one bore diameter is too short for the duct length - including the spigot/venturi.Closer to 2* bore seems to be better. Easier to transition better closer to 2* with an insert that becomes a male slip joint.
Good thanks Wob. So although it is a single exhaust port which would normally be best with the smallest area of the duct at 90% of the exhaust port window.
Because the RG50's single exhaust is more like a T or Tripple port the duct could be better at 75%. With the narrowest part at a distance of 2 times the bore diameter or 82mm.
I will start modeling this up, not sure if this is the right thing to do but I will start with the Mach sensor at 82mm and use the first 41mm part of the pipe to form the converging part of the nozzle.
wobbly
3rd January 2016, 11:31
No - I think a better solution would be to have the add on spigot at say 40mm long.
Its outlet will be the header round diameter, but for the first 1/2 or 20mm continue reducing the duct size down to the 75% number.
This will mean less filling will be needed in the actual cylinder duct and the smallest area point to place the sensor ( as this will now be the duct length ) , will be at 60mm.
From 60mm out to 80mm the duct in the add on spigot will diverge.
And this last 20mm diverging section will be the first element in the pipe input.
AndreasL
3rd January 2016, 11:53
Great TZ and Wobbly!
This will help a lot.
Grumph
3rd January 2016, 12:12
The easiest way to do this is with linisher its surprising quick, so be careful, I recommend practising on a old rod first.( I learnt that the hard way:laugh:)
The Air NZ workshop in CHCH used to do the peening (for beer money) as well as dynamically balancing the old Brit twin cranks for a lot of people not sure if it even still exists to this level anymore now likely a lot of stuff is outsourced.
The peening appears to give it a finish that resists minor corrosion not sure why.
Aviation Support Services at ChCh airport still do shot peening - but not for beer money...Most airports with any sort of ground support for aircraft work will probably have someone who can do shot peening.
husaberg
3rd January 2016, 12:14
Aviation Support Services at ChCh airport still do shot peening - but not for beer money...Most airports with any sort of ground support for aircraft work will probably have someone who can do shot peening.
What about the dynamic balancing?
Grumph
3rd January 2016, 12:22
What about the dynamic balancing?
Not at the airport to my knowledge. The guy in town who was really good - ex DSIR - sold his gear to Gav Hill (HPE). You takes your chances...
Barry Lynch can be persuaded to do static balancing. Couple of reconditioners have dynamic gear. Best in my experience is Coombes. I've used them for probably 30 years...
husaberg
3rd January 2016, 12:38
Not at the airport to my knowledge. The guy in town who was really good - ex DSIR - sold his gear to Gav Hill (HPE). You takes your chances...
Barry Lynch can be persuaded to do static balancing. Couple of reconditioners have dynamic gear. Best in my experience is Coombes. I've used them for probably 30 years...
Barry Lynch rings a bell was he ex st Asaph street?
Kickaha
3rd January 2016, 12:48
Barry Lynch rings a bell was he ex st Asaph street?
Beaumont Engineering
husaberg
3rd January 2016, 12:58
Beaumont Engineering
Wrong bell on the wrong street then.
nick gill
3rd January 2016, 16:55
Re polishing the beams on rods. When you do this you are cutting thru the highly compressed skin created by the forging process. The as forged skin may look like shit, but is in fact very strong. Polishing removes all the small imperfections and stress raisers, but then the rod MUST be re shot peined. The finished result will be much stronger again than the original as forged item, and lighter.
Hi Wob, Bob Mead (the Balancer you will know of) told me off for doing this to my Longtm rods yrs ago as he'd seen a lot of rods stress relieve over subsequent days.
But I've always wondered about the Samarin Rods, TM, or those Cristian Polverelli is using in the V4 (yummy!!), where they are fully machined:
https://farm2.staticflickr.com/1520/23512047634_dfd14896d1.jpg
They are forging/hardening/machining/peening/mechanically polishing/final honing? Sound too expensive....
Or are they using another methout that eliminates the forging step?
lodgernz
3rd January 2016, 17:16
The 75% area at the cylinder exit is just something I discovered after running hundreds of sims, most of them worked best with an oval to round transition in the flange that started with this area
and the pipe header diameter equalled the total effective area of the ports.
Its been tested and proven so many times now, by so many other people, that it should be the first mod to make to any T or tripple port engine.
Wobbly, you wrote this a long time ago, and it says the spigot final area should be 75% of the T-port or triple-port area, as is now well known thanks to you.
But I'm confused because it also appears to say that the area of the first header small diameter should be equal to 100% of the port area.
Doesn't this mean a step at the spigot? Or have I misinterpreted your post?
nick gill
3rd January 2016, 17:25
Maybe make something out of copper that is pressed into the exhaust duct for better heat transfer to the water jacket.
Hi TeeZee
The Copper may have a really high thermal conductivity, possibly as high as 400 W/m.K, or as abismal as 100 W/m.K depending on the alloy. IMO you'd be better to have a low thermal conductivity as possible, keeping the heat in the gas stream (this was my understanding - to cool the port itself but not the gas inside?). And if not, then aim for the closest coefficient of expansion to the parent material, i.e. G-AlSi9 etc, or Iron for durability.
I have the same issue as you and I intend to replicate my molding in CAD and have it Ti printed by Electron Beam Melting (higher density and more dimensionally stable than SLS), and in my case because the ex duct is IAME/Parilla TAG style (very short to flange)
http://www.out2win.com/catalog/images/RLV9228.jpg
integrate it as part of the exhaust header, so as not to risk it departing and causing a Fukushima. I'm probably not going to get a chance for some months but that is my intention. Kermit Buller has probably already tried this.
I do a lot of CNC machining of copper billet (http://www.luxrled.com) of Grade 110 [electrical] (400W/m.K), and 147 [free machining leaded] (150W/m.K), I can give you some round bar to play with - PM me.
I don't advise anyone go to the trouble of making Bronze heatsinks as as although they are copper rich the conductivity is usually only as good as 356A/G-AlSi9 or worse. Aluminium 6061 is the best compromise between machinability and thermal conductivity, the presence of silicon being the enemy for the task.
TZ350
3rd January 2016, 17:36
Hi TeeZee I have the same issue as you and I intend to replicate my molding in CAD and have it Ti printed by Electron Beam Melting (higher density and more dimensionally stable than SLS), and in my case because the ex duct is IAME/Parilla TAG style (very short to flange)
http://www.out2win.com/catalog/images/RLV9228.jpg
integrate it as part of the exhaust header.
I do a lot of CNC machining of copper billet of Grade 110 [electrical] (400W/m.K), I can give you some round bar to play with - PM me.
Your project sounds very interesting. PM sent, many thanks.
wobbly
3rd January 2016, 18:08
The Samarin and TM factory rods are fully CNC machined from billet, there is no hard skin as we see from the forging process.
Not having to do the forging process is a huge saving in die and manufacturing cost, for relatively small runs of product.
In this case the heat treatment is vitally important.
But for big factories the accurate as forged rod needs minimal machining, a big saving when huge numbers of lowly stressed parts are involved, and the heat treatment cost can then also be minimized.
Hot Rods as another example do both, forging then alot of machining, and then do the shot pein as well, and this proves economical ( and technically superior ) when reasonable run sizes are involved.
Re the port/duct areas.
First we have the effective port area at the bore ( that includes the cosine factor of its down angle )
Then we have the duct exit area = 75% of this effective port area.
Lastly we have a tapered divergent ( CNC ) transition spigot, that connects the ( usually oval ) small duct exit, to the round header entrance that is back to 100% of the port effective area we started with.
Simple and remarkably efficient.
lodgernz
3rd January 2016, 19:35
Ah. I get it now. Didn't click that the transition insert is divergent. Thanks Wobbly.
ief
3rd January 2016, 22:30
ps, didn't mean jbweld or the like but something like this (http://www.rexin-loettechnik.de) (english part of the site seems to be down)
Frits Overmars
3rd January 2016, 23:53
Peak Torque or Peak Power, I chose peak torque because that is where everything is working at its best... Here is a trace overlay of Mach numbers... It is interesting to compare them to the torque curve.Same here. There is no clear relationship between the Mach curves and the power curve at first glance, but you can see a direct correlation with the torque curve.
we might try an entirely different approach to the exhaust dam idea that incorporates Wobblys suggestion of using the insert to reduce the duct area at the flange face. Maybe make something out of copper that is pressed into the exhaust duct for better heat transfer to the water jacket.Copper is a better heat conductor than aluminium alright, but the stumbling block for the heat is not in the insert; it's in the transition from insert to cylinder, and there's not much you can do about that, apart from welding up the exhaust duct and then ideally opening up the material under the duct so that coolant can come into close contact with the new duct floor.
The Copper may have a really high thermal conductivity, possibly as high as 400 W/m.K, or as abismal as 100 W/m.K depending on the alloy. IMO you'd be better to have a low thermal conductivity as possible, keeping the heat in the gas stream (this was my understanding - to cool the port itself but not the gas inside?). And if not, then aim for the closest coefficient of expansion to the parent material, i.e. G-AlSi9 etc, or Iron for durability.That low-conductive duct would pass less exhaust gas heat on to the the cylinder, so the cylinder would stay cooler while the heat would stay on the inside surface of the duct. It would then neatly raise the temperature of the washed-through fresh mixture before this would get shoved back into the cylinder, ready to create the mother of all detonations.
The duct's coefficient of expansion might lengthen the exhaust system 0,1 mm more or less, compared to a different duct material. I would not loose any sleep over it.
Anyway, what matters in controlling clearances and avoiding stresses is not the expansion coefficient but the dimension change itself. So you would for example choose a high-silicon, low-expansion alloy for the hot piston and a higher-expansion material for the cooler cylinder in order to keep both dimension changes equal to each other.
First we have the effective port area at the bore (that includes the cosine factor of its down angle). Then we have the duct exit area = 75% of this effective port area.You knew I was going to react, didn't you Wob?:devil2:
First we have the blowdown area. I relate all other exhaust system areas to it; then I don't need to differentiate between 75% for a triple port, 90% for a single malt port, and so on.
Granted, establishing the blowdown area is not as simple as measuring the total exhaust window area; that is a clear factor in favour of your approach.
TZ350
4th January 2016, 10:52
318530
Christmas has been good to me, got an essential piece of workshop equipment, a La-Z-Boy reclining chair big enough to have an afternoon snooze in ......
318531
Now I can disappear out to the shed and only go back inside when called for meal times, "she who must be obeyed" is over joyed that I am out of the way.
wobbly
4th January 2016, 11:02
Sure did Frits,and I agree completely that we should be using the blowdown as a basis for all this,as its has a direct relationship to the power
capability available.
Now that we are seeing the real possibilities surrounding lifting the port floor, this is again making the port window area even more irrelevant so I need to
start generating a data point set to indicate the numbers we need to be looking at based on blowdown STA.
Add to this the duct length factors I detailed before and then real gains can be made with ease.
Neels has done an update to the EngMod RSW sim using the above numbers that will make your socks roll up and down.
We will see soon what he has come up with.
Re the Ryger, I have been monitoring the CIK published homologation site area, and sadly nothing has appeared yet.
But fear not, the instant it does, all will be revealed.
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