ESE's works engine tuner

[Bert]

I would like some video updates on the injected GP125.
GET TO WORK FUCK YA! It's the most interesting mod to date!

I want some video updates of the sidecar.... been waiting long enough.
GET TO WORK FUCK YA! the most interesting thread in the racing section.. :corn:

[Drew]

I want some video updates of the sidecar.... been waiting long enough.
GET TO WORK FUCK YA! the most interesting thread in the racing section.. :corn:

I shall oblige you today then sir. Have to take a break from the hospital visiting with the missus, the chairs are fucken terrible even in a private hospital!

[TZ350]

I would like some video updates on the injected GP125. GET TO WORK FUCK YA! It's the most interesting mod to date!

Yep keen as mustard ... the next move is to try and get it started on the dyno, but there is a bit of a backlog of dyno work to be done on the 50's before next weekends racing, so some time, soon as, after next weekend.

[TZ350]

I have a question about plug to piston top distance.

I had measured the 125 head and domes I got for domed pistons, two hemi head's with 0.7 squish would have about 8.7 distance from plug to piston dome top. But the domes I got have more volume and they would make 10.3 mm of distance, toroidal head's have a lower distance and I have one stock toroidal Honda RS 125 head but my bike does'nt seem to like it with the domed piston.

Is there any good baseline for this? Thanks
I would like a bit of discussion around this. I guess is important for everyone here.

Here you go .....

And if you left click on a posters name then click "View Forum Posts" you can search back and find all the interesting stuff they have posted.


To do a toroid properly you need to drop the plug tip approx 6mm from the piston crown.

Means welding the chamber and counterboring the plug seat face.
Very difficult to do repeatable and accurately unless done on CNC.
I model the piston dome and the head shape in SolidWorks to generate a solid then I have an accurate curve the toolpath follows and a calculated volume.


You dont really need the Ex timing to establish the head geometry, and yes the 6mm number seems to work with most " usual " combustion chamber geometries.
Avgas works with anything from around 192 to 202 Ex duration at around 15.8 full stroke.
Smaller bores or lower bmep setups can go 16.2, big bore oversquare or very high bmep like slightly less at 15.5, air cooled of course needs alot less.
As long as you hit the lower mechanical squish depth limit, then adjust the width to hit 38M/Sec MSV you will have good squish turbulence that helps the flame speed - reducing any tendency to deto
the end gasses.
That MSV number is meaningless in the context of all but hitting the head when within the normal rev limits, but as a guide it works every time.
The sharp bowl edge increases the flame speed, and a very deep angle away from that edge into the bowl is synergistic by pulling the turbulence further into the combustion space, again increasing the flame propagation speed,
over a wider band.
Pushing the combustion parameters this hard means a digital ignition is mandatory to balance the timing against the high peak cylinder pressure now being generated.


No free lunch today except that its all been done before and in most cases a guide is available.
It depends upon the stroke length, the piston weight and the crank integrity.
Suffice to say that a 125 single will usually go down to 0.65mm when spinning to 14000
A 250 twin like the RGV with a single middle bearing will go 0.75 spinning to 12,000
A 250MX type with 72mm stroke is OK at 1mm spinning to 11,000.
But I stress again, as I dont want the Honda faggots off their forum abusing me that the NSR wont rev if taken below 0.8mm - the ignition has to be optimised
to work with a combustion chamber that is designed correctly, and does actually do what its supposed to.
A stock PGM simply wont cut it - but then we wont be using HRC parts, so they just cant be any good at all, as everyone should realise.


Yep, looks fine.
The flat squish area should have 0.1mm taper upwards from the bore edge.
As I found the piston will clip the inner edge first when the vertical gap is at the mechanical limit for the rpm.
This is the sort of shape you are after.


There is only one rule grasshopper,NO radius from the squish into the bowl.
The other rule is to pull the squish down to the mechanical limit - ie probably around 0.7mm on an RGV then adjust the width to get around 38M/Sec MSV, usually 45 to 50%.
This generates good response and " torque" as you put it - but for sure will need a digital to retard the top end advance to get the overev back.

[2T Institute]

http://www.crp-racing.com/portal/images/stories/Kit-Honda-Lamellare/honda-disco-rotante-1.jpghttp://www.crp-racing.com/portal/images/stories/Kit-Honda-Lamellare/honda-disco-rotante-3.jpghttp://www.crp-racing.com/portal/images/stories/Kit-Honda-Lamellare/honda-disco-rotante-2.jpghttp://www.crp-racing.com/portal/images/stories/Kit-Honda-Lamellare/honda-disco-rotante-4.jpg

This has been posted before...... but there is another similar version.. maybe Indian or Chinese but i can't remember what it was......
http://www.crp-racing.com/portal/en/kit-honda-disco-rotante.html

There was the Mahindra engine made by Engines Engineering, was for all intents and engine designed by looking at pics of the RSA without actualy getting hold of a RSA to copy. There is still a few Euros outstanding apparently :whistle:

[husaberg]

There was the Mahindra engine made by Engines Engineering, was for all intents and engine designed by looking at pics of the RSA without actually getting hold of a RSA to copy. There is still a few Euros outstanding apparently :whistle:

Yes it was likely the Mahindra but i can't find the pics other than these. From the pic i seen some where it looked like a simpler set up re the drive to the disk than the RSA.
http://i45.servimg.com/u/f45/13/15/94/65/20091110.jpg
think it became the lochin/lambretta?

On further investigation the drive i am thinking of may be actually on the RUMI rear disk? Anyone got any pics of the disk drive set up?
<img src="http://i25.servimg.com/u/f25/13/15/94/65/la_tec12.jpg" height="240px"/><img src="http://i25.servimg.com/u/f25/13/15/94/65/la_tec11.jpg"height="240px"/> <img src="http://i25.servimg.com/u/f25/13/15/94/65/la_tec13.jpg" height="240px"/>

For Rob the Most sucessful arrow.
<img src="http://www.deraceheldenvanweleer.nl/index.php?PHPSESSID=bbobq0gv5ajsklgubq0c2ehnu0&action=dlattach;topic=166.0;attach=22274;image" height="410px"/><img src="http://www.deraceheldenvanweleer.nl/index.php?PHPSESSID=bbobq0gv5ajsklgubq0c2ehnu0&action=dlattach;topic=166.0;attach=22272;image" height="410px"/>

I have often seen this but never the story behind it.
<img src="http://www.deraceheldenvanweleer.nl/index.php?PHPSESSID=bbobq0gv5ajsklgubq0c2ehnu0&action=dlattach;topic=166.0;attach=17639;image" height="540px"/><img src="http://www.deraceheldenvanweleer.nl/index.php?PHPSESSID=bbobq0gv5ajsklgubq0c2ehnu0&action=dlattach;topic=166.0;attach=5582;image" height="540px"/>

[Myron]

The statement also seems at odds with what I have been working with in KZ2 kart engines.
These 125 engines have a U bend stinger dumping into a large muffler.
Two mufflers are available, one with the muffler perf a couple of mm bigger than the stinger ID, the other around 50mm ID.
The larger muffler would in effect create the conditions at the stinger end replicating dumping into atmosphere.
It also happens to add around 6 Hp at 14000 - so if the wave action within the stinger due to its length is having no effect, then what is causing this.
It certainly isnt the small muffler simply affecting the pressure in the pipe due to a flow restriction.
The length appears critical, so i am going to try adding length to the stinger inside the big muffler to see what happens ( this isnt a tech item by the way, and yes I put a venturi inside the stock stinger as well ).

Hello, first time poster. I'm not into buckets, but Two Stroke race engines in general. Wobbly is an acquaintance from another site. I agree with Wob. Two different approaches can be taken, to try to lessen stinger influences, or embrace them. Simply put, when pipe effects are phased correctly, the low pressure pulse emanating from the stinger can be phased with the tail end of the next suction pulse, creating what Wob may be experiencing.
Myron

[RomeuPT]

Here you go .....

And if you left click on a posters name then click "View Forum Posts" you can search back and find all the interesting stuff they have posted.

Ok TZ350, I kind a remember those post's, but those 6 mm are for a toroid. I wonder if the hemi is the same, thinking if the toroid brings to the flat piston the same height of the a 2mm dome piston.

Thanks for your research...

[Haufen]

Here you go .....

And if you left click on a posters name then click "View Forum Posts" you can search back and find all the interesting stuff they have posted.

Thanks TZ. I am curious to know the difference in those numbers when running pump fuel (ROZ 98) instead of Avgas. Do you happen to know if this has been covered here, already, too?

What I found was:


The issue that your test doesn't address is that with pump gas you may be able to get away with 13:1 com.
With AvGas its just starting to work properly at 15:1 and this attribute will always far outweigh any advantage flame speed or whatever may be contributing from the pump gas scenario.

The other issue is that unleaded fuel works best with plenty of advance, no com, and rich as hell.
AvGas loves com, loves running lean and hates advance, so you need to spend days on the dyno just optimising for the fuel.
Much better things to be doing in making a fast reliable race engine I believe.


Unleaded fuel to make best power likes to be rich and have plenty of advance with low com.
Thus in general a shorter pipe would be needed, as you say due to the lower egt.
But as usuall there is a fly in the ointment in that the FIM race fuel that needs gloves and a respirator, acts differently,and ends up with the same tuned length as was used with ELF124.
But the bulk pipe temp isnt what the egt probe reads in the header, its the average temp and is alot lower overall.

Unfortunately, I did not stumble upon any numbers for low com (well, maybe that is the 13 as mentioned in the post?) and plenty of andvance (35° at max torque? 25°? 20°?).

[TZ350]

Ok TZ350, I kind a remember those post's, but those 6 mm are for a toroid. I wonder if the hemi is the same, thinking if the toroid brings to the flat piston the same height of the a 2mm dome piston.

RomeuPT I dont realy know but Emess posted a possibly easier way of finding the good stuff posted by those who do.


... 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

[husaberg]

Reply to myself well it could be the Mahindra............
i found these pics
<img src="http://i48.servimg.com/u/f48/15/88/46/22/img_1714.jpg" height="280px"/><img src="http://i48.servimg.com/u/f48/15/88/46/22/img_1611.jpg" height="280px"/><img src="http://i48.servimg.com/u/f48/15/88/46/22/img_1613.jpg" height="280px"/>
<img src="http://i48.servimg.com/u/f48/15/88/46/22/img_1718.jpg" height="420px"/><img src="http://i48.servimg.com/u/f48/15/88/46/22/img_1720.jpg" height="420px"/>

[TZ350]

287316

Not been having too much luck with the 50.

So gave up and set the Beast up for its first EFI startup.

287317

Got the maps loaded and everything setup and it pretty much fired up straight away, ran for a bit then cut out.

Remembering the fuel pump does not like any air bubbles I carefully blead the fuel line to the pump and tried again.

It fired up easy as and ran for 15-20 seconds then it cut out again.

287318

I think the problem is in how I have the pressure regulator fuel return line setup. Its setup as a return to the suction side of the pump, any air/fuel vapor in the regulator return line will vapor lock the the pump.... :facepalm: .... Chambers tried to tell me but .......

Anyway it was good to hear the Beast kick into life, sure it ran rough and the induction noise was way worse than the exhaust, worse than anything I have heard before.

Could a harsh induction sound indicate good inlet suction action???? I have no idea.

And I don't have the faintest clue where the injection timing is in relationship to the transfer closing point either.

So a few things to sortout and quite a bit to learn, but it runs.

[Frits Overmars]

Trying to preheat the fuel, TeeZee? You may get bubbles allright, even if they are not air bubbles. Some fuel components boil below 50°C....

[TZ350]

Trying to preheat the fuel, TeeZee? Some fuel components boil below 50°C....

:laugh: yes I see your point but it is not as close to the chamber as it looks, everything is pretty loose so I can change things about easily.

[Flettner]

No, you must send the fuel back to the tank, separately. You must have a large flow pipe to the pump from the tank also a large flow pre filter and an high pressure after filter. Much fuel is traveling around the circuit. You do not want cavitation, you do not want any blockage or you engine will expire, quickly. Those little chinese pumps do not like any contamination / cavitation. Your engine relies heavily on this pump maintaining constant flow / pressure. I know you know this but just saying.

[TZ350]

No, you must send the fuel back to the tank,

Thanks for the tips, looks like I am off to the hose shop again tomorrow for a return line and Supercheap to see what filters they have. I am already using a big filter for a header tank for the pump but will get something to go after the pump.

[twotempi]

No, No. No you guys !!! Don't encourage him to pre-heat the fuel because he will get a large saucepan and try to do it on the stove element !!!!!!!!!!!!!!

[speedpro]

Totally agree about returning the pressure regulator outlet to the tank, though , , , I haven't quite done that myself. I have a secondary tank fed from the main bike tank. The outlet to the pump is from near the bottom, the regulator return is near the top, and the very top of this little tank is pulled up into a peak with an air bleed. Theoretically once it's all bled it should never get air in it and what little may eventually appear out of the fuel circuit will collect at the top of the secondary tank well away from the outlet to the pump. Haven't tried it yet but it should work and I'll bring it to bucket racing this weekend and hopefully not embarrass myself again.

[Muciek]

Hey guys, I would like to know what do you think about Power porting in engine that have reed valve in cylinder. In Bell book there are only few sentences about it , and he says to cut the piston to get around 200* of opening. Did someone know is there any formula to calculate appropriate degree of opening to get good results or get close to ballpark?

[Yow Ling]

I would not bother with a filter after the pump, I bthink it is just a hazard, you will have 40 psi fuel downstream waiting for a way to get out.
What purpose will it serve other than to catch the parts of the fuelpump as it wears out, if the fuel is clean going into the pump it should be clean coming out

[cotswold]

Thought this was clever

[Drew]

Totally agree about returning the pressure regulator outlet to the tank, though , , , I haven't quite done that myself. I have a secondary tank fed from the main bike tank. The outlet to the pump is from near the bottom, the regulator return is near the top, and the very top of this little tank is pulled up into a peak with an air bleed. Theoretically once it's all bled it should never get air in it and what little may eventually appear out of the fuel circuit will collect at the top of the secondary tank well away from the outlet to the pump. Haven't tried it yet but it should work and I'll bring it to bucket racing this weekend and hopefully not embarrass myself again.

Agghhh stink. I thought I was going to have something constructive to contribute. This bastard beat me to it.

Essentially you've created a surge tank I think. Air will end up at the top of it I imagine, as fuel sloshes away from the tank pickup and the pump is still scuking fuel from the second tank.

On a bike it's not as bad as in a car, but I should think it will still happen.

[jasonu]

Thought this was clever

How so? It looks like a sleeve and piston to me. What am I missing?

[Yow Ling]

How so? It looks like a sleeve and piston to me. What am I missing?

It grew up to be the Aprillia RSA125 ?

[F5 Dave]

So you googled Jamanthi too? Its as old as I am.

[cotswold]

How so? It looks like a sleeve and piston to me. What am I missing?

I've lead a sheltered life and have not seen one bolted on before

[husaberg]

How so? It looks like a sleeve and piston to me. What am I missing?


It grew up to be the Aprillia RSA125 ?


So you googled Jamanthi too? Its as old as I am.


I've lead a sheltered life and have not seen one bolted on before

Berts TZR100 Sleeve was a slipping from memory.....


Some would say I've seen the light; I say I'm temporarily blinded by actually finishing a days racing without a headache...
The TZR100 has gone under the bench until I can figure out what to do with the slipped sleeve.

.

Some of Jans collaborations
Jamathi, Piovaticci, Bultaco, Minarelli, Garelli, Rumi, Schuurman, Aprilia, Derbi..
https://lh5.googleusercontent.com/-Y9nX3ytL84M/S6G2T8IoUEI/AAAAAAAACc0/LbSlZE4T2vI/w904-h574-no/jamathiblok19741.jpg
https://lh6.googleusercontent.com/-0FwbGMazqBQ/S6G2UflBleI/AAAAAAAACc4/ieTQnsW6DTk/w878-h590-no/jamathiblok19742.jpg
https://lh4.googleusercontent.com/-vYTLP71xYJQ/SuqyLrGVPWI/AAAAAAAAAZw/tStjkF1CyCQ/w699-h470-no/1969.jpg
https://lh5.googleusercontent.com/-00l73KMtgOw/SuqyJcyf2xI/AAAAAAAAAZY/LQNnfPRtp_Q/w600-h294-no/1983.jpg
https://lh5.googleusercontent.com/-WkPwbFDDFaE/SuqyK4DNDKI/AAAAAAAAAZo/xVIaVXzG0vM/w692-h428-no/1976.jpg

[cotswold]

So you googled Jamanthi too? Its as old as I am.

no it came up on a different forum and it solves the slipping liner issue

[F5 Dave]

Better to cast them in. Or ideally plate if designing an engine this century, Liners are bad M'kay.:pinch:

[Bert]

Berts TZR100 Sleeve was a slipping from memory.....


Some of Jans collaborations
Jamathi, Piovaticci, Bultaco, Minarelli, Garelli, Rumi, Schuurman, Aprilia, Derbi..

yip Husa your on the money.
Some will recall Last years north island round in welly I had a few issues with the power valve (locking up and finally snapping the cables on the Saturday afternoon).
What seemed/turned out is it all got a bit hot (pump seal shagged) and gearbox full of water/oil, thus leading to the cylinder got very hot & the sleeve slipped down 1.5mm... Amazing it carried on going for the rest of the weekend (all be it shit) should have blown the head gasket/oring and filled everything with water. But given it was full of chunks, it didnt)...

Turned out no top lip on sleeve. So one needs to figure out what too do now. New sleeve or find a way to lock it in place..

It will be fixed and it will make a comeback...

[speedpro]

Turned out no top lip on sleeve.

That's friggin hard to believe. I'd be demanding my money back.

[jasonu]

I've lead a sheltered life and have not seen one bolted on before

Ahh now I see. Clever, maybe. Was it successful? Did that approach catch on?

[wobbly]

I must have been sheltered as well, I have never seen a sleeve that didnt have a step on the top for vertical location.
Maybe what is clever is the larger flange out from the combustion space to help heat flow to the finning.

[Grumph]

That's friggin hard to believe. I'd be demanding my money back.

Not uncommon to have no top lip. I assume this was sleeved back to 100 from 125. Much cheaper to use a parallel sleeve and less machining involved. Millions of diesels around the world reconned like this
they don't give troubles unless they're radically overheated.....as i see this one was.

It may be possible to use liquid Nitrogen to shrink the sleeve in place and restore it to correct alignment.

[Grumph]

I must have been sheltered as well, I have never seen a sleeve that didnt have a step on the top for vertical location.
Maybe what is clever is the larger flange out from the combustion space to help heat flow to the finning.

i looked at that and wondered if the cylinder was cast with the top of the water jacket open at the top and the liner extension closed it off...Casting would be much easier.
The danger with that layout of liner is possible cold seizure at the top due to different expansion rates top/bottom.

[Drew]

i looked at that and wondered if the cylinder was cast with the top of the water jacket open at the top and the liner extension closed it off...Casting would be much easier.
The danger with that layout of liner is possible cold seizure at the top due to different expansion rates top/bottom.That could take a while to diagnose. I imagine it would just pinch the ring and run like shit, as soon as you started to put the motor under load without warming it up proper.

I'd go through twenty slugs before I figured that out!:facepalm:

[F5 Dave]

. .

Turned out no top lip on sleeve. So one needs to figure out what too do now. New sleeve or find a way to lock it in place..

It will be fixed and it will make a comeback...

Yeah that just seems lazy way to do it. Perhaps reseat the sleeve & run a countersunk bolt into the front skirt at the bottom. Once in the cases it can't back out & CS stops it winding forward & dropping out. That there's now a small hole in the bore at the bottom of the stroke is no biggie.

[jasonu]

Millions of diesels around the world reconned like this
they don't give troubles unless they're radically overheated.....as i see this one was.
.

Diesels don't (usually) rev to 13000+ rpm.

[speedpro]

The other issue for a sleeve without a method to locate it vertically is what does the head gasket seal on? With my turbo even with a lip to stop the sleeves dropping I still had problems with the thin sleeves cracking the lip off and then the bottom part of the sleeve dropping down a mm or so. Luckily never enough to snag a ring. The other thing was that the sleevesd couldn't be installed with too much interferance as the blocks could crack between the sleeve bore and the oil gallery where it went up the stud hole. Some primo "LA Sleeve Co" sleeves sorted it all out. My CB360(470cc) cracked the top off a sleeve as well. Fixed that by selling it to Rob for $100.

[husaberg]

Better to cast them in. Or ideally plate if designing an engine this century, Liners are bad M'kay.:pinch:

From memory the modern Foul strokes don't even need the plating now. Chevy (i think vega) in the 70's started the cast with lots of Silicone or something then etch out the Aluminum later, i think Honda and Yamaha are doing the same now on the R1 and the CBR250 although they might be using MMC or some other ceramic......

[Yow Ling]

To have a sleeve made locally, not ported about 120 to 150
These imported sleeves 100 for 3, even have top lip

57 od 49 id 120 long

287351

[mr bucketracer]

From memory the modern Foul strokes don't even need the plating now. Chevy (i think vega) in the 70's started the cast with lots of Silicone or something then etch out the Aluminum later, i think Honda and Yamaha are doing the same now on the R1 and the CBR250 although they might be using MMC or some other ceramic......the honda sp1 - 2 and so on run on the aluminum barrel , but thats a four stroke for ya (-:

[Bert]

Yeah that just seems lazy way to do it. Perhaps reseat the sleeve & run a countersunk bolt into the front skirt at the bottom. Once in the cases it can't back out & CS stops it winding forward & dropping out. That there's now a small hole in the bore at the bottom of the stroke is no biggie.

That was about the same idea/plan we settled on. But no rush now as the foul stroke will get some use and we have had a lot of success getting ponies to have fun with. But I won't be leaving it for too long....


The other issue for a sleeve without a method to locate it vertically is what does the head gasket seal on? With my turbo even with a lip to stop the sleeves dropping I still had problems with the thin sleeves cracking the lip off and then the bottom part of the sleeve dropping down a mm or so........

Don't forget we have a replaceable head insert and orings everywhere. Need to take some more photos.


To have a sleeve made locally, not ported about 120 to 150
These imported sleeves 100 for 3, even have top lip
57 od 49 id 120 long


yea got a few sitting on the shelf, purchased after the first one was done. Still in the back of my mind is what Wobbly & rob discussed about 400 pages ago re alloy sleeve and coating. Would work out about the same. Also wandered if a conversion to a 125 air cooled option....

[Kickaha]

Still in the back of my mind is what Wobbly & rob discussed about 400 pages ago re alloy sleeve and coating. Would work out about the same. .

I costed that at about $800-900 a few years ago for a four stroke

[husaberg]

yea got a few sitting on the shelf, purchased after the first one was done. Still in the back of my mind is what Wobbly & rob discussed about 400 pages ago re alloy sleeve and coating. Would work out about the same. Also wandered if a conversion to a 125 air cooled option....

Around here i guess it was on one of my log in pages......if you click the arrow it should take you to the ball park

The GP and RG400 cylinders with their single exhaust port don't allow enough blowdown time area to make decent power. But I could sleeve an aircooled GP125 cylinder and add a T or tripple exhaust port, but thats not so easy to do with a RG400 cylinder as there is not much meat around the exhaust port area on one of those.



I am not sure what the cause of ND's problems was, or what the sleeve he used was made of, or if he fitted an iron sleeve within the original steel sleeve and had a bad thermal path. I just don't know much about how he went about things but I have heard he made a new sleeve and has pretty much got on top of the long track reliability issues now.

230183 230184 230185

My plan is to use a large diameter, thick walled, plated alloy sleeve and bore the cylinder out as much as possible to maximize the heat transfer area between sleeve and alloy cylinder jacket. And of course it will be put together with CPU heat transfer paste.



I like your idea of using an RG150 cylinder as that would allow a thick sleeve like you suggest and possible a water gallery through the sleeves exhaust bridge too.

Wobbly has been planning everything for me around sleeved down RGV250 cylinders, but I like the idea of a larger sweeping bend up to the transfer port.

230180 http://www.2stroke-tuning.nl/media/pdfjes/porting.pdf

Yamaha in their SAE paper said that the number one thing that affected power delivery was the angle of the port entering the cylinder and number two was the radius of the transfer duct, then the upswept angle of the port roof.

I will get Wobblys opinion on the shape and suitability of the RG150's port ducts which look a little different to the RGV's.

Mike are those sleeves the Akunar ones?

[Yow Ling]

Mike are those sleeves the Akunar ones?

yes they are

[husaberg]

yes they are

I was looking there myself yesterday.
http://www.akunar.com/CYLINDER_SLEEVES.htm


A while ago i posted an Excel shreadsheet in Dutch that someone had made up based on a simplified Frits pipe formula
Frits pointed correctly out it should have detailed the restrictor

Here is a better version in English as well.
http://www.underdogsracing.com/fospipe.html

[Flettner]

Briggs and Stratton run straight alloy bores!

[Yow Ling]

Briggs and Stratton run straight alloy bores!


mmmm briggs and Stratton EFi on E80
damn needs to be based on motorcycle engine

[TZ350]

mmmm briggs and Stratton EFi on E80

damn needs to be based on motorcycle engine

No ... only a non competition engine, so a side valve brigs lawnmower motor should be OK. They had alloy bores and flash chromed piston and rings, supercharged and running EFI with E80 fuel and a CVT transmission ... now there is a thought..... :)

[koba]

No ... only a non competition engine, so a side valve brigs lawnmower motor should be OK. They had alloy bores and flash chromed piston and rings, supercharged and running EFI with E80 fuel and a CVT transmission ... now there is a thought..... :)

"Engines must be derived from non-competition motorcycles"
Sorry to be the rules Lawyer...

[husaberg]

Hey guys, I would like to know what do you think about Power porting in engine that have reed valve in cylinder. In Bell book there are only few sentences about it , and he says to cut the piston to get around 200* of opening. Did someone know is there any formula to calculate appropriate degree of opening to get good results or get close to ballpark?


Question for the panel

In the Bell book he mentioned modifying the two crankcase ports in a CR125 cylinder (the old cylinder reed model which has two small ports with link the reed cavity with the crankcase)
He closed them with filler and then shortened the piston skirt to achieve 230 degrees inlet duration.

I did the same mod on my old H100 which has similar ports and a windowless piston but never got around to testing it.
I always wondered how much difference it would actually make and why.

Has anyone ever tried it?
He said he achieved an extra HP or so with the mod.




Edit - re the so called "power port" idea.This was developed as a tuning aid back when engines made no power at all, and running a bigger piston port timing, along with forcing inflow to be pushed thru the boost port, just happened to add a Hp or 2 on top of none to start with.
What we find now is that cylinder reed engines always end up being power limited by the effective STA that can be obtained by cutting holes in pistons, adding big Boyesen ports and even then adding floor ports.
All this is attempting to get the inflow around and or thru the piston that is in the way alot of the time.
That is why case reed is ultimately better when done properly.

I see you have also posted the question on the Pitlane thread........

[pete376403]

From memory the modern Foul strokes don't even need the plating now. Chevy (i think vega) in the 70's started the cast with lots of Silicone or something then etch out the Aluminum later, i think Honda and Yamaha are doing the same now on the R1 and the CBR250 although they might be using MMC or some other ceramic......

Chev Corvair - the flat 6 - was the high silicone ally block.

Anyone other than Kawasaki done the electrofusion cylinder? The description I read long ago was that a wire of some special metal was placed in the cylinder down the bore, and a very high electric current applied. The resultant bang (think of a fuse) sputtered the metal into the cylinder walls.
IIRC this was used in the KX cylinders, among others

Electrofusion cylinder
Improves heat transfer for consistent power output
It is porous so it holds lubrication well
It is hard so it resists abrasion and seizure
Allows closer piston-to-cylinder clearances for more power


http://en.wikipedia.org/wiki/Kawasaki_KX250#Electrofusion_cylinder

[husaberg]

Chev Corvair - the flat 6 - was the high silicone ally block.

Anyone other than Kawasaki done the electrofusion cylinder? The description I read long ago was that a wire of some special metal was placed in the cylinder down the bore, and a very high electric current applied. The resultant bang (think of a fuse) sputtered the metal into the cylinder walls.
IIRC this was used in the KX cylinders, among others

Electrofusion cylinder
Improves heat transfer for consistent power output
It is porous so it holds lubrication well
It is hard so it resists abrasion and seizure
Allows closer piston-to-cylinder clearances for more power


http://en.wikipedia.org/wiki/Kawasaki_KX250#Electrofusion_cylinder



Also added a Apitec and GKN blub missing a page or two bugger maybe someone has the last ones.
What interested me was the squeeze form liners i am not even sure if they still make then as they aren't listed o the either web site.
The site is interesting in which the repairs are carried out i was wondering why i couldn't strip then tig up the whole cylinder and then machine it and re-coat it rather than a sleeve anyway.

Re coating i am not suggesting to send stuff oversea when we have a place in NZ.
Plus yes it would be easier to sleeve a cylinder.

http://www.poetonaptec.co.uk/default.htm
http://www.gkn.com/Pages/default.aspx

Sweet at least it was still chevy re the coating, if you click on the arrow you will see Mahle did it as well likely first.

[TZ350]

"Engines must be derived from non-competition motorcycles"
Sorry to be the rules Lawyer...

Thanks ... saved me, I was getting all excited about lawn mower engines there for a moment.

[Flettner]

Oh, I don't think that's a problem, I've seen B&S engines in a motorbike frame before ( mini bike ), that counts!

[husaberg]

"Engines must be derived from non-competition motorcycles"
Sorry to be the rules Lawyer...


Thanks ... saved me, I was getting all excited about lawn mower engines there for a moment.

See the S in engines there is also one in the Apendix D
for class Max engines capacity........ i guess Billy might have overlooked that :nono::lol::bleh:

Sorry i could not, Not appreciate the irony of that

[Ocean1]

Oh, I don't think that's a problem, I've seen B&S engines in a motorbike frame before ( mini bike ), that counts!

My old man even made two, which counts as a production machine, surely?

In fact both were eventually repowered with Wankels. :shifty:

[Flettner]

Ha Ha, a production run!
Well, here we are getting into " my old man " stories, my dad had two 25HP wankels on a single seat helicopter back in the early 70's . Joined by a tooth belt drive, each engine had a sprag clutch just if one stopped you see. It would have to rate as one of the most frightening experiences of my life, rotors spinning ( I was sure one would detach ) with two wankels at full noise. We used to hide behind the shed when testing was under way, I could see it ending very badly one day. And it did.

[twotempi]

Mercedes Benz had a process that used rollers ( a bit like rollers instead of abrsive stones of a hone ? ) to high-pressure force a slurry film on to an aluminium cylinder bore. Does anyone know anything about this ??

[F5 Dave]

Well continuing the testing I always find what should work isn't a given. With the Ignitech Wobs fav RGV coil swapped in do something queer, it dropped the revs and power slightly. So I might of got a bit back by changing the timing, but tried running a bit cooler and it dropped off so swapped back to Grady old coil and it came back.

also tried my flash Harry Rsomething NGK race plug & lost a bit of power over BR9ES. Again maybe I need to compensate to get best results, or maybe my head shape just doesn't like it.


Ring seal might be better after using torque plates, power came up, but must retest to see if that is what it was, also water cooled barrel so that could be some.

[wobbly]

The flash NGK plug ( as long as it is the same heat range ) in a back to back test always outperforms any other plug when in a stressed combustion scenario.
Super high bmep with very high pressures and temps needs every Joule or whatever of energy in the gap,to initiate a clean burn, and having an Iridium centre and Platinum fine wire ground strap
makes it much easyer for the spark to ionize and begin the burn.
Using a trick plug in a non highly stressed environment is the same as running leaded race gas in a lawnmower - a complete waste of time and money.
Same with flash combustion chamber shapes like a flat top bathtub or toroidal with a sharp edged,wide squish into the bowl.
None of this is effective in creating HP unless the end use setup is pushing the limits to the max, and the better combustion control, or deto resistance, is actually needed for the thing to physically survive.

[F5 Dave]

Yeah I've seen big changes for seemingly small things before but I've also seen no changes for known better setups. Maybe I'm not pushing the limits, but I'm not far off what Mike has had on his MB in the past. Same revs and I think I'd be there. Mine isn't well developed yet, still a bit peaky to claim I've done a good job. But this was always my quick &dirty setup. Just it's been going on longer than I'd hoped.


I'll try again when I'm nearer.

[Frits Overmars]

...I've also seen no changes for known better setups.A two-stroke is like a combination lock with 10 digits, Dave. You won't notice if a digit is right or wrong until you've found them all....

[F5 Dave]

Yes, I've returned from the dyno more times than not returned to an original setting.:pinch:

but latest jump was following Wob KT idea of torque plates and heating the barrel. My MB engine just seemed to respond to that well, but haven't measured ring seal again, must be better.

was confused by the coil how it dropped peak revs. Somehow advancing timing perhaps.

[Drew]

Yes, I've returned from the dyno more times than not returned to an original setting.:pinch:

but latest jump was following Wob KT idea of torque plates and heating the barrel. My MB engine just seemed to respond to that well, but haven't measured ring seal again, must be better.

was confused by the coil how it dropped peak revs. Somehow advancing timing perhaps.

Higher resistance in the better coil and quicker response perhaps. That's a really short version of what I'm thinking because I'm posing from phone.

Are you not running ignitech on yours Dave?

[F5 Dave]

yeah its igni with Wobs 2 into 1output configuration. running a largely straight curve with a 1*drop after peak but need to calibrate the knockgauge & set it up a bit better, just wanted a constant till I sort some other issues.

The watercooling of barrel seemed to work well, but the pump I'm running is a little underrated. Problem is the thermistor is in the RS rad but doesn't stick down far enough compared to mechanical one, may have to move it into the head to see what is happening tempwise.

[wobbly]

Do you mean straight line retard, or a flat line.
A flat line is for sure not even close to whats needed on any 2T setup??

[2T Institute]

also tried my flash Harry Rsomething NGK race plug & lost a bit of power over BR9ES. Again maybe I need to compensate to get best results, or maybe my head shape just doesn't like it.


Have tested it on the track? At the start of the race you will notice a massive difference. If your engine prefers a ES plug there is something not right.

[F5 Dave]

Flat as a starting point, but I need to try a slope as it drops off pretty fierce. Presumably that will change once I got the Solenoid carb on and include closing the PJ.

What would you suggest as a reasonable retard after peak starting point? 5* drop over 1000rpm? Hope to play with this later this or next week

[F5 Dave]

Have tested it on the track? At the start of the race you will notice a massive difference. If your engine prefers a ES plug there is something not right.

No, this was 3 consistant runs on the dyno, swap plug & 3 more compared. No changes to ign timing.

Domed piston, 16:1 Av, short bathtub, sharp edges.


Hmm, sorry must be a BR9EGV, not ES sorry about that.

But the R7376 plug was a 10

[F5 Dave]

Do you mean straight line retard, or a flat line.
A flat line is for sure not even close to whats needed on any 2T setup??

This was an old post from way back when I was getting interested in getting an ignitech

. . .
You have to be careful when using retard to heat the pipe in the overev.
If you continue the retard slope too far,especially if the motor then continues to make serious power - the egt will continue to rise with rpm, and you then end up running a richer main to suppress the now too high egt.
This means you are using fuel to cool, not burning it to make power.
You must flat line the ignition retard as soon as you can in the overev, to stabilise the egt when running full throttle at those peak revs.
. . . .

Maybe I have misinterprted the last bit?

[TZ350]

Hi there,
the results of the third round of the 13/14 season of AMCC bucket racing from yesterday are attached, for publication in the newsletter & website.
Regards,
David Diprose

287540

And Printable PDF.

287539

Team ESE rider Rick52 took two more wins in the A grade points racing, and I hear that he was the only one to run in the 29's yesterday.

So the finishing order was 2T 4T 4T 2T in the 1st A grade points race and 2T 2T 4T 4T in the 2nd, looks like the time is coming when anyone wanting to win A grade races will have to think about building themselves a fast 2T.

[F5 Dave]

. . .looks like the time is coming again when anyone wanting to win A grade races will have to think about building themselves a fast 2T.
Fixed that for ya.

[speedpro]

Cully mentioned at the previous meeting that they were going to sort out something for those riders that transferred from one grade to another. My son was relegated at that meeting from B grade to C grade after he changed bikes and was a bit slower on the new one. He's back in B grade now but is missing any B grade points from that previous meeting which is affecting his placing in the points table.

What is going to happen and when?

[wobbly]

You will get just as much change in power with a differing ( better ) heat range as you would from a better ( expensive ) nose configuration.
If an engine is happy with a 9 plug then it cant possibly be anywhere near the limits of any parameter - power,egt,timing, bmep.
A fast RS125 will deto its tits of if not running a 10.5, but as a general rule always run the hottest plug heat range the engine will tolerate.

Re the timing " curve ", I was referring to the retard slope from where it comes onto the pipe, and peak power.
This cant be a flat line, but can easily be a straight line from say 28* to 15*.
The comment about flat lining the retard past peak power assumes of course that the timing has dropped sufficiently past peak, to get enough heat into the pipe to get the overev you want/need.
But then any more retard will simply create the need to over fuel to get the egt numbers back in the ballpark.

Here is the 400 F3 bike ignition, and any more retard past peak power at 11,000 and the egt climbs thru the roof - needing very rich jetting that kills the peak numbers.
The flat line allows just enough heat to get it to rev past 12,000 if needed.

[jasonu]

Cully mentioned at the previous meeting that they were going to sort out something for those riders that transferred from one grade to another. My son was relegated at that meeting from B grade to C grade after he changed bikes and was a bit slower on the new one. He's back in B grade now but is missing any B grade points from that previous meeting which is affecting his placing in the points table.

What is going to happen and when?

Mike are you saying the points he gained in C grade should be added to his points gained in B grade?

[Drew]

Mike are you saying the points he gained in C grade should be added to his points gained in B grade?That's sorta how I read it, but figured I got it wrong. Bottom line, miss rounds in whatever class for whatever reason, stiff bikkies.

[F5 Dave]

You will get just as much change in power with a differing ( better ) heat range as you would from a better ( expensive ) nose configuration.
If an engine is happy with a 9 plug then it cant possibly be anywhere near the limits of any parameter - power,egt,timing, bmep.
A fast RS125 will deto its tits of if not running a 10.5, but as a general rule always run the hottest plug heat range the engine will tolerate.

Re the timing " curve ", I was referring to the retard slope from where it comes onto the pipe, and peak power.
This cant be a flat line, but can easily be a straight line from say 28* to 15*.
The comment about flat lining the retard past peak power assumes of course that the timing has dropped sufficiently past peak, to get enough heat into the pipe to get the overev you want/need.
But then any more retard will simply create the need to over fuel to get the egt numbers back in the ballpark.

Here is the 400 F3 bike ignition, and any more retard past peak power at 11,000 and the egt climbs thru the roof - needing very rich jetting that kills the peak numbers.
The flat line allows just enough heat to get it to rev past 12,000 if needed.

Thanks that gives me something to work with. presumably as I add the solenoid closing I would back the final curve rate off as the lean condition combined with too much retard would be doubling up? ie: in your example if you had solenoid carbs the last drop would be less severe perhaps?

[speedpro]

That's sorta how I read it, but figured I got it wrong. Bottom line, miss rounds in whatever class for whatever reason, stiff bikkies.

He didn't miss a round. He was relegated against our wish to C grade where he got some points. I was not suggesting anything as simple as giving him his C grade points in B grade. Cully said they were going to sort out something, I want to know what that will be. With the timing system we now use it would not be too hard to check everybody's race times and see where he would fit in "if" he had been in B grade on that day and award points accordingly. If he would have been last in B grade it will be real simple. As he was relegated that is exactly where I would actually expect him to place - last.

[TZ350]

presumably as I add the solenoid closing I would back the final curve rate off as the lean condition combined with too much retard would be doubling up?

As I understand it, the aim of closing the power jet during over rev is to maintain the correct air/fuel ratio otherwise it goes over rich with the increased airflow through the carb. (so this is one of the things you have to have in mind when you choose the ballance between the main and power jet)

And the extra heat in the pipe comes from shifting some of the heat energy of combustion, from the combustion chamber to the pipe by retarding the ignition.

[TZ350]

Cully mentioned at the previous meeting that they were going to sort out something for those riders that transferred from one grade to another.

287547

I know nothing ....

But will bring it to Cullys attention and maybe a PM to Chambers would help too ...

[speedpro]

As I understand it, the aim of closing the power jet during over rev is to maintain the correct air/fuel ratio otherwise it goes over rich with the increased airflow through the carb. (so this is one of the things you have to have in mind when you choose the ballance between the main and power jet)

And the extra heat in the pipe comes from shifting some of the heat energy of combustion, from the combustion chamber to the pipe by retarding the ignition.

My take on the powerjet being turned off is that you do actually want to lean it off at the top to heat things up. You have to be careful with a carb setup for unleaded as the powerjet will be on the larger size. If you are running Avgas and already running leaner than on unleaded, and then switch off the powerjet, things could get ugly real fast. For leaded fuel and associated jetting the powerjet needs to be smaller in comparison so a smaller amount of fuel is switched off.

[Yow Ling]

Mike are you saying the points he gained in C grade should be added to his points gained in B grade?

maybe grades should have a ratchet mechanism built in, it's not like he suddenly became a worse rider. so instead of instant demotion maybe you have to be crap for a few consecutive meets before getting downgraded

[cotswold]

So the finishing order was 2T 4T 4T 2T in the 1st A grade points race and 2T 2T 4T 4T in the 2nd, looks like the time is coming when anyone wanting to win A grade races will have to think about building themselves a fast 2T.[/QUOTE]

You forgot to mention F5 2T, 2T, 2T :2thumbsup

[F5 Dave]

My take on the powerjet being turned off is that you do actually want to lean it off at the top to heat things up. You have to be careful with a carb setup for unleaded as the powerjet will be on the larger size. If you are running Avgas and already running leaner than on unleaded, and then switch off the powerjet, things could get ugly real fast. For leaded fuel and associated jetting the powerjet needs to be smaller in comparison so a smaller amount of fuel is switched off.
Wob had suggested a PJ size for Av & I've converted the KX carb with that size to start with.


Thus experience has shown that as leaded fuel works best with a lean condition at peak power, we only need to switch a small jet just past peak - to increase the pipe temp and
thus give better overev.
In the Keihin numbering this is in mm dia and switching off a .35 is perfect.
When running unleaded, as the GP bikes have for years, the fuel likes to be rich at peak to create the best power, thus we need to switch off alot of fuel flow to increase the pipe heat quickly enough.
In this case a .65 is needed to do the job.

[TZ350]

Page 840 ...

[husaberg]

Can't remember where it was from and i was looking for something else.......


I have not seen much written about power jets. Thought I'd share what I know, and hope others can augment it. Perhaps the most succinct definition of a power jet comes from A. Graham Bell's book Two-Stroke Performance Tuning.

"The Powerjet has the effect of enriching the mixture at full, and close to full throttle, and then only when air velocity is high enough to create a vacuum of sufficient intensity to discharge fuel. It is, in effect, a load sensitive enrichment device."

Kay Nissi (sp?) at Mikuni America calls the power jet a "Band-Aid". He says it allows you to run a leaner main jet (for better part-throttle response) while maintaining a safely rich mixture at high RPMs and WOT.

The electrically-operated power jets used on later-model TZs employ a solenoid to enable and disable the flow of fuel. I have observed the power jet solenoid's behavior with my data acquisition system. Under most operating conditions the solenoid is de-energized permitting demand-based flow of fuel through the power jet. However at very high RPMs, the solenoid is energized by the CDI computer, thus *stopping* the flow of fuel. This leans the mixture increasing the temperature of the exhaust gas. Note: This behavior ensures a fail-safe mode of operation. If the solenoid fails or should become unplugged, the mixture will remain rich.

This assessment is confirmed in SAE paper 983072, Measurement of Exhaust Gas Temperatures in a High-Performance Two-Stroke Engine: "Air/fuel ratio may also be managed to influence the exhaust gas temperature. On the test engine, the carburetor was fitted with a solenoid-controlled jet. Below 11700 rpm the jet is open and additional fuel flows to the engine. Above 11700 rpm, the control system actuates the solenoid which closes the jet. This results in a leaner air/fuel ratio which increases the combustion and exhaust gas temperatures, thereby improving the exhaust tuning."

The electrical part of a power jet (the solenoid) sometimes goes bad. A bad power jet solenoid is difficult to diagnose. The engine just runs a bit rich on one cylinder. Therefore, it is a good idea to test the solenoids occasionally.

There are several ways to test the power jet solenoid. On TZs which have a battery, all you need to do is switch the bike on. The computer in the CDI box performs it's power-on self test which includes cycling the power valve servo-motor and the power jet solenoids. Using a piece of radiator hose, you can listen for two distinct "clicks" emanating from each of the solenoids. The first click is produced when the solenoid is energized -- retracting the pintel (this would stop the flow of fuel). The second click is produced when the solenoid is de-energized -- extending the pintel (allowing the flow of fuel).

If you unscrew the solenoid from the fuel-handling part of the power jet (as if you were going to replace the jet itself), you can actually see the pintel retract and extend.

On TZs that don't have an internal battery, you can perform the same test by using Yamaha's test lead (P/N 3TC-82117-00) and an external battery.

To test a power jet solenoid that is off the bike, simply apply 12 volts DC to it. (The solenoid is not polarity sensitive.) You should see the pintle retract and extend each time you apply and remove power.

Because it is next to impossible to repair the solenoid if its electrical connection comes off internally, it is prudent to zip tie the cable to the body of the power jet. This preventive maintenance provides strain relief and should keep the cable from becoming detached in a crash or due to rough handling.

Although OEM power jets invariable come fitted with an opaque hose, I prefer to run a translucent hose. (I use an alcohol resistant fuel line manufactured by Bing and sold through Aircraft Spruce and Specialty.) This allows you to verify there is fuel in the float bowl and also lets you see the fuel level.


The tech term for what Frits is describing is Superposition of the Ex pulse.
This is easily described in a sim, where a residual pressure ratio is seen sitting at the Ex port when it is opening.
The "new " pulse is added to this residual, and a very large pressure ratio exits down the duct to the header.
The larger the initial ratio, the larger the amplitude of the wave in the diffuser - this creates a deeper depression around BDC, and it is this that initiates the biggest mass flow
from the transfers.
The lower Ex timings of 190 and below create larger residual pressure ratios,over a wider band, and thus these work with a good pipe design to use "resonance" to increase band width and also peak power.
Big problem though is this whole concept is at odds with maximising blowdown to allow good peak power and more importantly, overev power.

The sim shows RGV100 making serious power with the superposition pulse going down the duct - off the scale.

Re the trombone pipe results you did sims for TeeZee.
Look carefully when you say it seems to affect the top end "more ".
At 9000 the lowest reading is 13 Hp, the highest reading is 17 Hp, thats an increase of 4 Hp, thats 31% more power in the bottom end, that then allows the thing to rev to 17,000.
Seems a not bad result.

Re the powerjet temp result you mentioned.
The effect of the solenoid powerjet is as you described - this I only discovered recently with a datalogger that I could set the sample rate of the EGT high enough to read the temps quick enough - along
with some exposed junction probes.
I was testing a RS125 on the dyno and it was making NO power past 12500, looking at the data you could see the egt drop from 640 C to 580 in around 400 rpm.
After fixing the fact some idiot had left out the rpm plug in the loom, the solenoid now switched on at 12200, and the temp stabilised at 650 past 12500 and the thing than reved out to 13500 +.
So the powerjet switching isnt making the mixture "lean"as such, it is simply maintaining the correct mixture, and thus the temp in the pipe.

I have looked into the "overangled" issue that creates a problem when using the electronic powerjet carbs.
Its worth plenty of horsepower to keep the intake dead straight, and I am building a KTM250 for a open class kart at present.
I have bored the 38 to 40.5 and mounted it on a straight rubber manifold.
This sits the carb too steep, in that the siphon hole for the powerjet circuit in the side of the bowl is only just "underwater" when sitting static.
Get some serious G forces working and this will be sucking air.
It looks easy enough to Araldite a small external tube running forward to the front of the bowl that has plenty of fuel height above it at all times.
Or maybe drill a hole thru at an angle forwards, and press a small brass tube into this to collect fuel from the front side of the bowl.
I will pic this when I have done it.

When using a simple powerjet nozzle the tip position matters in that no flow will occur until the slide is well past the exit hole, and there is sufficient airflow
to drag fuel up the feed tube above the bowl level.
With the aftermarket add ons and the ones as used by Lectron you can shorten the dump tube so that the flow will only occur at high slide openings,as well as high air flow.
These also have a built in "lag "control in that it takes time for the fuel to rise up the tube and dump out the exit into the air stream.
With a solenoid controlled setup all this is pretty much irrelevant as the flow can only occur when the solenoid is not powered up, and this
is TPS as well as rpm dependant inside the ECU program..
The carbs as used on the MX bikes has the dump tube very low in the bore as they added and subtracted fuel at low slide positions in those bikes.
For a race engine I bend the tube up to around 1/2 bore, as this is where the exit is on the Kehin SPJ carb for RS125/RS250 Honda.
And the general setting is the solenoid is powered up ie no flow below 4000 and 60% TPS and is powered up again at around 12400 to lean off the mixture and increase revon.
This causes a problem with Ignitechs that are used with only a capacitor, as at startup the solenoid is powered up, dragging all the voltage out of the ECU, so I convert the ECU output
to a 3 step truth table, and have the setting such that below 1500rpm the solenoid isnt powered.

Aha, I see. I think I got it now, Frits.
If the powerjet is positioned in the middle of the venturi or at a lower point, that will affect how much it will flow, correct?

I remember both Lectron and Mikuni aftermarket PJ kits' instructions, saying that the end tip of the pj should be around the middle of the carb.
Yet the Keihin PJ of the carbs for the mx250 models is down low! Position would also affect which fraction of the flow becomes more rich or not, or that doesn't matter??

255006


254941

Made an adjustable PJ out of a model aero engine carb needle jet for controlling the PJ. Now to get one of those solenoids the Husaburg posted to shut off the PJ for a bit of extra over rev.

Made some progress with the shorter inlet tract and expect to get the lower mid range back again with a bit of fiddling with the carburation.

Just a little bit more and the single exhaust port engine with the RS pipe will be very close to EngMod2T's predicted power output.

254940 125cc rotary valve with a 24mm carb and air cooled.

Measured 31 rwhp (estimated 34 crank hp) on the dyno tonight, red line is last night before the inlet tract was shortened and the jetting/ignition adjusted.

I have ordered one of Wobblys special kitset "A" Kit Pipes for a Suzuki GP125 ..... so hopefully 1 or 2 more hp and a wider spread of power. Then there is the ATAC idea for better low end.

Nope. It is drawn by the dynamic pressure at the fuel exit points in the carburetter. And that pressure depends on the mean air flow velocity along those exits.
Air flow velocity is at its highest in the center of the narrowest part of the inlet tract, so the location of the fuel exit will make a difference. And by mean air flow I mean (air flow into the engine + backflow)/2.
You see, more than enough variables; more than enough differences between the exit points of the fuel flow through the main jet and the flow through the power jet.

Re the tiny bleed hole in the TZ powerjet tube - I always thought that this was a good idea to emulsify the fuel as it exited the dropper.
But years ago i did some wet tests on the flowbench with a VCR video camera ( pretty trick shit stuff back then ).
The Mikuni was a horror scene when played back slo mo,with huge "gobbs" of fuel exiting the main and powerjet.
We then stuck on a Lectron - wow, lovely fine mist of fuel from the back of the flat needle face - and it flowed 12% more air - size for size with a venturi 2mm smaller behind the slide.

Next is the current state of TeeZees GP125, here is the latest dyno curve digitised with 16% added to simulate crank power.
Then there is the sim with an actual RS early model pipe.
Then there is the new pipe of my design.
Of most interest is that in this case the sim is giving slightly too much crank power - but the shape and peak point are all but perfect.
I would be confident now that any change in the sim, would be reflected in reality on the dyno.
In my experience the later Dynojets like a twin roller 168 with Eddy current load control to slow the acceleration rate down ,seem to read around 5 to 10% lower
so this would put the sim and the dyno reading very close, as the shape is spot on now.

You have to be very carefull with the switch point and the run time on the dyno.
The switch point is dead critical to 100rpm,so i always set it too high initially and make sure that the dyno is loading the acceleration rate to be as close to that on track as you can.
This gives the pipe time to heat up and affect the power over the top, as it would in reality.
On a RS250 dropping the switch point from 12800 ( std) to 12400 gives easily another 800 rpm of virtually no power drop past peak.
On the track,if the rider can feel the switch point ( it feels like hooking another gear)the jet is too big,when its right it should be seamless and just keep reving out.
Leaded fuel is the opposite to unleaded, in that as leaded likes to run lean - you can only use a small powerjet and thus only switch off a small amount.
A leaded engine works best with around 35 to 38 PJ, the unleaded fuel can switch a 60, in Keihin numbering, as the crap fuel makes best power at peak when quite rich..

And something that I scraped from the net.........

""The solenoid control on TZ type powerjets really just shuts off fuel flow to the powerjets right at the top of the rev range to lean the mixture off to increase the over-rev once you are past peak power.

I don't have the solenoids plugged in currently though as I find they work well enough for my current needs with the powerjets simply responding to venturi vacuum pressure in pretty much the same way as the oem 3MA powerjets work.""

233787233788

And here is a picture of the carbs and what I can make out, a dyno graph without, and with the power jet solenoids shutting off (red line) and extending the over rev.

So it looks like you can use an electric power jet like a standard one and when the carburation is sorted, try switching it of by activating the solenoid at or just after peak power and see what happens with the over rev.

The FPE superkart engine that won the NZ road title at Manfield a few weeks ago makes 92 RWHp on the Dynojet 168 I use.
Still not quite as good as the RS250 setup we did that won at Laguna Superkart Worlds a couple of years ago.

The powerjet carb is controlled by the Ignitech with a combination of throttle position and rpm in a "truth table".
In general the solenoid is activated with 12V ( no fuel flowing) below 4000 rpm and 75% throttle on the TPS.
Above 75% and around 12400 rpm it is activated again to lean off the fuel curve over the top of the pipe.
Looks like you will be able to reverse the fuel exit, blocking off the hole on the throttle bore side, and take off fuel from the outside bung, thru a needle jet and into the top of the venturi next to the slide.

Recently I got myself (Ebay) a 38mm carb with Throttle PS and Electric PJ from a motor crosser.

Wobbly told me that on those the PJ nozzel is to low and starts to flow to soon for a road racer and the MX ones are hard to tune.

230481

I couldn't afford to buy a good second hand TZ or RS unit. So I figure that moving the discharge nozzel.

230483

And adding an adjustable jet from a large model aero engine could be worth a try.

230482

On the dyno I have seen how a leaner mixture rev's on further and how richining it up for best power the over rev drops off.

I think that as the rpm goes up the mixture strength on an ordanery carb at max rpm goes over rich.

And at the moment I think the idea is that the PV is shutoff after peak power to get back to the correct mixture and by retarding the ignition at the same time extend the over rev, but I am sure there is more to it.

I would love to know more about how this type of carb should be used and/or setup.

The modern take on powerjets is to turn them off after peak power to extend the rev range. This assumes that you are happy for your engine to rev that much further past peak power & on many buckets perhaps this is not so good unless you have uprated the crank assembly. The jet will start to flow, depending on its position. Some don't seem to work well without an airbox if they aren't very prominant, or perhaps if the suction isn't so much (putting big carb on a smaller cylinder). In some cases they are best blocked off presumably if the air jet doesn't match very well & is tending to increasing richening with airflow as it is.

With all the talk about wanting to utilize only a couple of gear changes per lap, I would have thought that the solenoid powerjet was a gift from heaven.
A late model well tuned RS125 will rev to around 12400 if the PJ is disabled,turn the PJ function back on and it will go to 13800+.
Its so simple and you retain exactly the same lower rev power,but with easily another 1000rpm to work with you have the choice of adding teeth on the back, getting better acceleration from torque multiplication, or keeping the same gears - but increasing the terminal speed.
And from the dyno curves I have seen, most of the 100 buckets with short stroke lengths, arent even beginning to stress the bottom ends - with less peak rpm than the 54.5mm stroke 125 bikes or karts that will easily run to 13000 all day.

Ok now we have a stepper motor controled power jet........

The 'high compression brickwall' is no longer as hard as it used to be. With leaded fuel the compression ratio was 19,5; nowadays it is about 15. The 'brickwall' arose from the high expansion ratio (which is identical to the compression ratio). The higher this ratio, the more the burnt gases in the cylinder cool down before they enter the exhaust, thus lowering the resonance frequency of the exhaust system.
Riders complained that the engine would not rev, especially not in the lower gears, where the revs rose so quickly that the rising wall temperature of the exhaust pipes could not keep up with them. So you had cold exhaust gas and cold pipes.

The problem was to a large extent solved when the solenoid-controlled on/off-power jets were replaced with stepper motor-controlled jets that could continuously adjust mixture strenght, allowing the engine to rev more freely.

229455

This is it. The stepper motor itself originates from a Fiat Uno where it regulates the idling rpm

Regarding the Aprilia RSW/RSA125 single, Jan Thiel told me that in seven years of testing the racing department had not been able to establish which was best: low or high inertia. I would choose low.....

Frits Overmars

To give you an idea of the main jet / power jet ratio: typical RSA-values are main 220, power 120. That means the flow area of the power jet is about (120/220)^2 = 0.3 times the flow area of the main jet. And don't shut the power jet until well past the rpm of maximum power or you will risk a maximum seizure.

Imagine the valve passes 60 cc of fuel per minute, but the engine only needs 30 cc. How would you go about that? You could open the valve for 30 seconds and then shut it, but by that time the engine may have drowned.
Open it for one second, close it during one second, open it for one second, sounds more sensible, doesn't it? That is why I quoted the valve's frequency: 13 Hz.
That means it can open and close up to 13 times per second. This again means it could open for 1/13 of a second and close the rest of the second, or open for 12/13 of a second and close during 1/13 s, or everything in between. And of course it can stay completely open or closed; enough possibilities to govern the mixture.

The ignition timing does not have to be changed when you use an electronic power jet. But both the ignition timing and the powerjet timing are means of influencing the exhaust gas temperature. A late ignition and/or a lean mixture both cause a higher EGT, so you can match the exhaust resonance frequency to a rising engine rpm.
And if you have that power jet available, the ignition does not have to do it all by itself anymore, so you can search for a timing that gives a better overall result.

When Jan Thiel was developing the Derbi DRVE (now known as the Aprilia RSA125) it turned out that with the engine in the frame the carb was tilted too far forward.
Jan then tried a Keihin that could cope better with the tilt-angle. But there was a contract with Dellorto...
I do not recall the exact date that the electronic power jet was first used. Must have been after Witteveen left the building at the end of 2004 (when he realised that he would be losing Jan Thiel to then-rival Derbi) because Witteveen was always opposed to the powerjet even though Jan Thiel had been asking for it for ages.
The first powerjet version had a stepper motor borrowed from a Fiat Uno where it used to govern idle rpm. In the Dellorto it operated a needle valve.
It was later superseded by a Keihin solenoid valve. Keihin just used it as an open/close valve but with some electronics of their own Aprilia turned it into a pulsating valve (13 Hz). The picture shows those Keihin valves on Simoncelli's Gilera RSA250.

Area 1.6 main = 2.010, less area 0.35 = 0.0962.
Main jet should now be 1.56,closest is 1.55 with the powerjet .
Try this without switching first to check equivalent egt to original setup.

Its a big one sorry all this talk of piggy back circuits.
These curcuits can also be used in numerous ways partically like a couple of them.
<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if !mso]><object classid="clsid:38481807-CA0E-42D2-BF39-B33AF135CC4D" id=ieooui></object> <style> st1\:*{behavior:url(#ieooui) } </style> <![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]-->
Refer: Silicon Chip January 2007 This kit stops the air conditioner in your car from taking engine power when accelerating such as when you're overtaking or going up a hill. It automatically switches the air conditioner's compressor off when the engine is at a high throttle setting and will allow the compressor to run with low throttle even when the cabin temperature setting has been reached. It also automatically switches the compressor off at idle. When the throttle position is normal the compressor will operate normally. The kit features an override switch, an LED function indicator and is supplied with PCB with overlay and all electronic components. > Recommended box UB3 HB-6013.
http://www.jaycar.com.au/productView.asp?ID=KC5437&CATID=76&form=CAT2&SUBCATID=965#11
<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]-->
This kit operates a relay when a preset temperature is exceeded and drops-out the relay when temperature drops. The relay included is capable of switching small currents only, so a larger relay or switching device should be employed if switching mains voltages or heavy currents. Ideal as a thermostat, ice alarm, hydroponics applications, etc. A small trimpot is used to adjust the cutout temperatures for the relay in the range of approx -30 to +150 degrees celcius. €Kit includes NTC thermocouple.

http://www.jaycar.com.au/productView.asp?ID=KG9140&CATID=76&form=CAT2&SUBCATID=965#11
<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]-->
http://www.jaycar.com.au/productView.asp?ID=KC5424&keywords=auto&form=KEYWORD
http://www.jaycar.com.au/productView.asp?ID=KC5378&CATID=76&form=CAT2&SUBCATID=965#11
http://www.jaycar.com.au/productView.asp?ID=KC5195&keywords=auto&form=KEYWORD
http://www.jaycar.com.au/productView.asp?ID=KC5435&keywords=auto&form=KEYWORD
http://www.jaycar.com.au/productView.asp?ID=KC5442&keywords=auto&form=KEYWORD
http://www.jaycar.com.au/productView.asp?ID=XC4226&CATID=76&form=CAT2&SUBCATID=965#11
http://www.jaycar.com.au/productView.asp?ID=KC5443&keywords=auto&form=KEYWORD
http://www.jaycar.com.au/productView.asp?ID=KC5376&CATID=76&form=CAT2&SUBCATID=965#11
http://www.jaycar.com.au/productView.asp?ID=KC5485&CATID=76&form=CAT2&SUBCATID=965#11
http://www.jaycar.com.au/productView.asp?ID=KC5377&CATID=76&form=CAT2&SUBCATID=965#11
http://www.jaycar.com.au/productView.asp?ID=KC5444&CATID=76&form=CAT2&SUBCATID=965#11
I mentioned 555 curcuit earlier. Most sensors give output in voltages 1-5 volts something along the lines below will enable a sensor to say pulse a powerjet?

One of the most fundamental problems in robotics is DC motor speed control. The most common method of speed control is PWM or pulse width modulation. Pulse width modulation is the process of switching the power to a device on and off at a given frequency, with varying on and off times. These on and off times are referred to as "duty cycle". The diagram below shows the waveforms of 10%, 50%, and 90% duty cycle signals.

As you can see from the diagram, a 10% duty cycle signal is on for 10% of the wavelength and off for 90%, while a 90% duty cycle signal is on for 90% and off for 10%. These signals are sent to the motor at a high enough frequency that the pulsing has no effect on the motor. The end result of the PWM process is that the overall power sent to the motor can be adjusted from off (0% duty cycle) to full on (100% duty cycle) with good efficiency and stable control.
While many robot builders use a microcontroller to generate the required PWM signals, the 555 PWM circuit explained here will give the novice robot builder an easy to construct circuit, and good understanding of pulse width modulation. It is also useful in a variety of other applications where the PWM setting need only be changed occasionally.
The 555 timer in the PWM circuit is configured as an astable oscillator. This means that once power is applied, the 555 will oscillate without any external trigger. Before the technical explanation of the circuit, let's look at the 555 timer IC itself.
http://www.dprg.org/tutorials/2005-11a/index.html

[TZ350]

I have been looking for Wobs old PJ posts too.


The solenoid Powerjet does lean off the BSFC curve BUT, what you need to get is that all it is doing is returning the fuelling to much closer to optimum.

Its not really "leaning it out "as such,it is dumping more of the available heat energy in the fuel - into the pipe, speeding up the wave action and thus extending overev available.

I remembered the first bit but had not joined the dots connecting it to the second bit.


PWM control of the powerjet is a very sexy use of technology,slowly ramping off the fuel flow against rpm, but in reality using a simple rpm controlled switched solenoid work perfectly fine.
Yamaha and Honda have used the switched powerjet since forever, its reliable and does the job.
Only issue you need to address is the jet size and switch point ( along with TPS value ).
Running Avgas as we are still allowed to do, means that the tuning is based around getting high egt numbers to create good power, with lots of com and advance - unleaded is the opposite..
Thus experience has shown that as leaded fuel works best with a lean condition at peak power, we only need to switch a small jet just past peak - to increase the pipe temp and
thus give better overev.
In the Keihin numbering this is in mm dia and switching off a .35 is perfect.
When running unleaded, as the GP bikes have for years, the fuel likes to be rich at peak to create the best power, thus we need to switch off alot of fuel flow to increase the pipe heat quickly enough.
In this case a .65 is needed to do the job.
On the dyno or on the track it is easy to tell if the switch point is a little too low, as it feels exactly like the bike has changed into another gear past 6th.
It jumps forward when the solenoid kicks in - making the fuel curve lean, too early.Do this enough - and bang.
Its critical to 100rpm, and is working perfectly when you dont feel it happen - the power just keeps going.
To do it on the dyno you have to run the bike in 6th to simulate the acceleration rate as seen in that gear on the track, and is easy to do running back to back run ups.
Changing the rpm number 100 at a time, lower in the Ignitech, reprogram on the fly and run again.
If the rpm is too high - nothing happens, as there isnt time for the heat to affect the pipe wave speed.


You must take into consideration the fuel being used, and how the factory engineers approached the problem.
Unleaded ( FIM that needs gloves and a respirator ) will go to 15:1 but must be run VERY rich to achieve best power with that level of com.
Leaded was run up at 19:1 in GP engines and at the end of the day the result was that the advance curves changed very little.
The big advance was in using the powerjet solenoids.
The unleaded scenario uses BIG powerjets ( 60 + ) to turn off the rich mixture past peak power.
The leaded setup was very lean at peak power, so only needed small ( 35 ) powerjets to keep the pipe temp up, over the top of the pipe.
Later of course that bastard Thiel came along and did the clever thing of PWM controlling the powerjet, thus even closer continuously matching the A/F ratio to the pipe
temp needed for max power.
Makes me sick just thinking about how clever he was, and how advanced the results became.
We are all just wankers floundering around in the mire of a mediocratic 2T wasteland - buckets.


I believe that the better fuel atomisation at the expense of the correct fuel curve would work on a 4T.
But as a 2T will throw its piston toys out of the cot at the first hint of a lean condition you have to correct the fuel curve to get the egt numbers progressively rising then stay stable in the overev.
Atomisation takes a back seat to A/F ratio accuracy with a well tuned 2T.
The FCR is a dead cool piece of kit - every circuit is very sensitive and responds immediately and logically to any small change.
1/4 turn on the idle air or fuel will raise or lower idle by 200 rpm straight off.
One main jet is exactly 40* temp change every time - great when you are watching everything in realtime on the dyno and data logging screens, for any indication of an issue or needing to correct a small hole in the delivery.

[Rick 52]

Cully mentioned at the previous meeting that they were going to sort out something for those riders that transferred from one grade to another. My son was relegated at that meeting from B grade to C grade after he changed bikes and was a bit slower on the new one. He's back in B grade now but is missing any B grade points from that previous meeting which is affecting his placing in the points table.

What is going to happen and when?

Onto it now Mike, this is all still very new and not yet perfect but is close, brilliant to get lap times and results printed out within minutes of the race finishing .
Any questions or suggestions can be emailed to any of the Auckland bucket committee .

Very happy with my results this weekend, I am hoping to keep up these results for all the work ESE has done helping with my bike :)

[TZ350]

TZ the Belzona product you used on the piston, What was it?
I have found an epoxy that is good to 2000F or 1100ish C Meant to be fuel resistant as well?

Please tell me more about this epoxy and where can I get some?

[husaberg]

Please tell me more about this epoxy and where can I get some?




Have a look at the products yourself something, well for almost everyone.

http://www.aremco.com/products/

the one that caught my eye initially was this.http://www.aremco.com/product/a15/ but used in other applications.....

ten carrot actors

Never used it or no idea where to buy it i seen it in a Mag and Googled it it seems it can withstand EX and such like but its all from the seller's info rather than third party. THe company seems legit make refactory stuff and all that kind of stuff.......


Pyro-Putty®
These high temperature ceramic and metal-filled pastes are ideal for repairing pinholes, warps and cracks in manifolds, headers, exhaust pipes, mufflers, and more. Pyro-Putty metal repair compounds bond tenaciously to cast aluminum, cast iron, steel, and stainless, and are easy to apply, cure, machine and clean up.
Pyro-Putty® 1000-K Kit
1400 °F for Cast Aluminum Repair
8 oz Powder, 4 oz Liquid
Pyro-Putty® 2400-K Kit
2000 °F for Cast Iron, Steel, Stainless
8 oz Paste, 4 oz Thinner

[TZ350]

Thanks .....

I am looking for something better than Devcon for sealing the exhaust port dam in my next cylinder.

[Gigglebutton]

Thanks .....

I am looking for something better than Devcon for sealing the exhaust port dam in my next cylinder.

Could I weld it Rob?

[husaberg]

thanks .....

I am looking for something better than devcon for sealing the exhaust port dam in my next cylinder.

tig...............screw.........

[TZ350]

Could I weld it Rob?

Thanks, but screw and glue looks like an easy repetable way of doing it.


tig...............screw.........

The last one was held in place with a couple of screws, and that seemed to work OK.

287553287554

But I suspect the Devcon glue I used to seal it will burn away in due course. I like the exhaust port dam idea and want to give it another serious go.

[TZ350]

Tim sent the MyLaps link below.


Onto it now Mike, this is all still very new and not yet perfect but is close, brilliant to get lap times and results printed out within minutes of the race finishing .
Very happy with my results this weekend, I am hoping to keep up these results for all the work ESE has done helping with my bike :)


Hi there,
the results of the third round of the 13/14 season of AMCC bucket racing from yesterday are attached, for publication in the newsletter & website.
Regards,
David Diprose

287540

And Printable PDF.

287539

Team ESE rider Rick52 took two more wins in the A grade points racing, and I hear that he was the only one to run (only just under 30's, F4 race 2) in the 29's yesterday.

So the finishing order was 2T 4T 4T 2T in the 1st A grade points race and 2T 2T 4T 4T in the 2nd, looks like the time is coming when anyone wanting to win A grade races will have to think about building themselves a fast 2T.

Hi all,
The results of Round 3 are now on Mylaps. You can get straight to them with this link: http://www.mylaps.com/en/events/956487
Tim

[F5 Dave]

This PJ stuff is all becoming a moot point atm. I don't know what sort of happy pills were being slipped into my weetbix when I dummied up the manifold on the engine on the bench, but I wish they would start again as there is no way this KX carb is going into the RS frame without a fairly major cut & shut.

Problem is the case reed conversion is too low so I'd need to run the PWK at a 40 degree angle which ain't going to happen, or accept a bit of a bend & some unwanted length as a compromise but at least get the PWK carb cw solenoid. . . except the frame needs a rethink. It could almost work if I assembled it & fit the engine to the frame. . .but that means dropping the engine for a jet change & even I think that's unworkable.

So now I'm stuck with the poxy RGV carb & trying to think how to make an external Solenoid PJ conversion. That bit is easy(ish) enough, but the tricky bit is mounting it to the carb where it wont get broken during a jet change (small window to pass through) or made sturdy enough not to leak given wear & tear.

Pass the grinder.

[Flettner]

Put a throttle body on it, don't bother with the carb. Throttle body much more compact.

The F9 is losing it's EFI, a backwards step. Seems it's not in the "spirit of the era" if I want to keep racing it in VMX. Fair enough, we will teach them ( VMX pre 75 ) a lesson in how to hot up a rotary valve engine even with a carb on it. Out to the pattern shop to make up a new barrel with modern porting, eye ports etc. More than one way to skin a cat, apparently.
I'll show them " spirit of the era"!!

[speedpro]

That shock mount crossmember is a problem for sure. I have looked at all sorts of options like cutting it out and moving the shock to the side and even rotating the engine and mounting it forward with the cylinder near vertical, possibly with a jackshaft. Moving the engine forward needs more investigation though I see problems with chain geometry and possibly clearance to the front wheel

[speedpro]

Or use a pumper carb

[F5 Dave]

Well I sidestepped the shock problem with the Case reed conversion (as long as the carb isn't too tall). Only problem is you need a smaller carb than the KX & ideally downdraft like the RGV Mikuni. FCRs are huoooge 'case they don't care about minimising the area under the carb on a foul stroke.

[bungbung]

http://www.youtube.com/watch?v=QgMgV3eDDvA

12 sec quarter. I wonder what the combined rider/bike weight is?

[Drew]

RGV Mikuni. You want one? I've got a couple here.

[F5 Dave]

Actually, ahh heck PM sent.

Pity MC28s weren't proper solenoid carbs cause they were downdraft (32s). not sure how physically big they are either.

[husaberg]

\ but I wish they would start again as there is no way this KX carb is going into the RS frame without a fairly major cut & shut.

Problem is the case reed conversion is too low so I'd need to run the PWK at a 40 degree angle which ain't going to happen, or accept a bit of a bend & some unwanted length as a compromise but at least get the PWK carb cw solenoid. . . except the frame needs a rethink. It could almost work if I assembled it & fit the engine to the frame. . .but that means dropping the engine for a jet change & even I think that's unworkable.

So now I'm stuck with the poxy RGV carb & trying to think how to make an external Solenoid PJ conversion. \


That shock mount crossmember is a problem for sure. I have looked at all sorts of options like cutting it out and moving the shock to the side and even rotating the engine and mounting it forward with the cylinder near vertical, possibly with a jackshaft. Moving the engine forward needs more investigation though I see problems with chain geometry and possibly clearance to the front wheel

Kel and Bren already sidestepped the issue.
Now You to are scaring me..its bad enough me head won't fit.
<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=267738&d=1344240782" height="340px"/><img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=231839&d=1297413329" height="340px"/>

[F5 Dave]

its an issue. With your taller reed position you will have better options. Nigels RG150 engine/carb fits in ok, or so it seems, he had to do a bit to make the engine itself squeeze in.

[husaberg]

its an issue. With your taller reed position you will have better options. Nigels RG150 engine/carb fits in ok, or so it seems, he had to do a bit to make the engine itself squeeze in.

I have got both here courtesy of TZ, i will post a pic of both side by slide. the KX has a venturi inserted for 24mm throat.
I think the rear mount of the NSR engine will prevent a short short straight intake without a remote float anyway.

<img src="http://3.bp.blogspot.com/_kJOOykmUBK0/SpcUxh7XNRI/AAAAAAAAAM8/tsvRAQPNW28/s320/100_1067.JPG" height="340px"/><img src="http://1.bp.blogspot.com/-6v_kfwry8ck/UWqGyHzBs6I/AAAAAAAAGlk/VQZOTcMQx14/s400/TheTRXproject_My_Honda_NSR_125_JC20_update_Cylinde r_dismount_003.jpg" height="340px"/><img src="http://i.ebayimg.com/t/HONDA-NSR125-ENGINE-BOTTOM-END-GEAR-BOX-GEARBOX-CRANK-NSR-125-JC22-03-/00/s/MTIwMFgxNjAw/$(KGrHqF,!h8F!DNm5OMyBQB(rV,8Uw~~60_35.JPG" height="340px"/><img src="http://i18.ebayimg.com/06/i/001/2c/73/5193_35.JPG?set_id=800005007" height="340px"/>

[TZ350]

The F9 is losing it's EFI, a backwards step. Seems it's not in the "spirit of the era" if I want to keep racing it in VMX.

287583

Sorry to hear you have run foul of the Luddites ...http://www.kiwibiker.co.nz/forums/images/smilies/facepalm.gif and have to remove the EFI.

But many thanks for showing that good home brew EFI is possible on a 2T, some of the posts and video of your dyno runs.


284277284278

EFI YZ250, (the graph is in mph because I could not easily get an ignition timing signal for rpm, next time).

284276284279

EFI Kawasaki F86M 350 Big Horn from the 70's.

284275

Yamaha blue line, Kawasaki red.



http://youtu.be/UEQli7nuak4


Here is ball valve and EFI at work. Interesting how the variable rotary valve housing needed to be controlled differently to get rid of the unwanted torque dip around 4 to 5 thousand. Thanks to Rob for sorting this out, I thought I knew a bit about rotary valve engines but after this run at ESE under Robs guidance, I am definitely the apprentice.


http://youtu.be/ifSEql1X4R0

[Frits Overmars]

Did you consider the giant air bubble in the cooling system above the red line?

[husaberg]

Did you consider the giant air bubble in the cooling system above the red line?

Yip after you said about it. It has a NSR250 front head on it at the moment. The NSR125 one Lozza sent over likely wont fit the NSR250 cylinder.
(Thanks Bren for checking that for me after i told him to buy one cause it would:facepalm:)

But i plan on using this one anyway.

But it is the talking about it stage... i need a engine to be ferried down here.............
Before anything can be nailed down.....

[TZ350]

This PJ stuff is all becoming a moot point atm. as there is no way this KX carb is going into the RS frame without a fairly major cut & shut.

So now I'm stuck with the poxy RGV carb & trying to think how to make an external Solenoid PJ conversion.

287590


use a pumper carb

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Team ESE have two 50's running pumpers.

Rick had the same sort of room issues with his TF125/RS but now uses a pumper. He took the last four wins at Mt Wellington using a 24mm Tillotson HL360A.

The 50's run the same Tillotson and 6lb pop off, my 125 was 9lb and I am unsure what Ricks is but probably around 9 too.

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With a solenoid from Jaycar an adjustable jet and some cleverness you could fit an electric power jet to it too.

[F5 Dave]

That first picture with carb on engine would make me concerned Husi. I think you are not going to have space.

MC28 looks good. Or is it MC21?

[F5 Dave]

The 100 is wc so want to run decent size as allows.

[TZ350]

Pumpers come in bigger sizes, much bigger sizes.

[F5 Dave]

Had a quick look at Tillson a while back but not much jumping out.

[husaberg]

That first picture with carb on engine would make me concerned Husi. I think you are not going to have space.

MC28 looks good. Or is it MC21?

21 i guess... Rob will know for sure.
There is plenty of stuff about them on the NSR.com site. Apparently some are better than others and they flow real well for what they are.
A mate had a huge Pumper off a Jet ski on his MB100 and it worked real well. But over fueling on over run was a issue Kart track hairpins were ugly and dangerous when it chimed back in)
but i think i had sent Rob some stuff Jennings did to cure that with the 34mm Macullochs on his 350 Kawa twin.
Yes the inlet looks a bit of an issue with the rear mount.......I will have to wait and see........
Maybe Fletner could cast me up a set of cases to fit the CVT, 100cc Aprilia "like" cylinder and through in a variable disk:msn-wink:

[TZ350]

Had a quick look at Tillson a while back but not much jumping out.

287595

How much carb do you need, this is a racing Tillotson with remote jet adjustment.

Yea .... na as they say, but if your serious about power, an old slide carb could be worth a look.

287596

They are typically 28-32mm and the pumper parts look like Tillotson so should be easy to get.

[TZ350]

21 i guess... Rob will know for sure.

No not sure, as I went through a phase of buying a lot of different carbs off the net looking for a way to get the best from the 24mm rule.

287597

In the end I got my best results by modifying the humble 24mm OKO. They are so easy to hold in the lathe and machine, there is lots you can do with one of these.

Unfortunately not much use to F5 Dave.

[wobbly]

I am coming to Auckland this weekend for the final round of the Kart Champs, so i will bring the NSR engine and parts with me.
Mat Hamilton can bring it back down to CHCH in the big VW van with the karts.
If you mount the engine well in your frame Husa, you can delete the top mount altogether, look at Chambers RG50 - giving plenty of room above the gearbox for a dead straight inlet
with RGV carb.

One other point here as well - I have been waiting for 6 months to get a shipment from Ignitech, they wont reply to my emails and I have 5K worth paid for and pissed of customers.
I rang Jim Lomas in Czech to get him to talk to them, but no luck - yet.
Anyone know someone that speaks Czech.

[F5 Dave]

That's not good news, I'm squireling away $50 notes (ok I'm about to put the 2nd one in) into a box in the garage so I can't spend it, & selling stuff to buy one for the 50. Maybe when I have enough you'll have got the shipment.

Try calling them, must be someone who speaks Engrish there.

[F5 Dave]

287595

How much carb do you need, this is a racing Tillotson with remote jet adjustment.

Yea .... na as they say, but if your serious about power, an old slide carb could be worth a look.

287596

They are typically 28-32mm and the pumper parts look like Tillotson so should be easy to get.

If I had that much spare for a carb I'd be buying a Smartcarb for my GasGas. Not that they haven't had some teething problems.

[RomeuPT]

I am coming to Auckland this weekend for the final round of the Kart Champs, so i will bring the NSR engine and parts with me.
Mat Hamilton can bring it back down to CHCH in the big VW van with the karts.
If you mount the engine well in your frame Husa, you can delete the top mount altogether, look at Chambers RG50 - giving plenty of room above the gearbox for a dead straight inlet
with RGV carb.

One other point here as well - I have been waiting for 6 months to get a shipment from Ignitech, they wont reply to my emails and I have 5K worth paid for and pissed of customers.
I rang Jim Lomas in Czech to get him to talk to them, but no luck - yet.
Anyone know someone that speaks Czech.


that´s sad. I have an ignitech and always wondered if I had a problem they you be ready to help.

Hope you get what's yours.

[husaberg]

I am coming to Auckland this weekend for the final round of the Kart Champs, so i will bring the NSR engine and parts with me.
Mat Hamilton can bring it back down to CHCH in the big VW van with the karts.
If you mount the engine well in your frame Husa, you can delete the top mount altogether, look at Chambers RG50 - giving plenty of room above the gearbox for a dead straight inlet
with RGV carb.

One other point here as well - I have been waiting for 6 months to get a shipment from Ignitech, they wont reply to my emails and I have 5K worth paid for and pissed of customers.
I rang Jim Lomas in Czech to get him to talk to them, but no luck - yet.
Anyone know someone that speaks Czech.

That would be ubber cool.........
I have League over there on the 12 and 13 OCT. I think the BOB is the following weekend.But i am sure i can get over there to pick it up before that anyway.
I hardly speak English. So no help with the Czech sorry...
I will have to look at chambers one. The Frame i have has been modified for a YZ250 or something.

I guess this is how you mean.

And the one I liked most of all, a RG50 in a Honda RS frame. One of F5 Daves engines fitted by RMS engineering.

The RG50's rear engine mount slotted straight into the RS rear mount and the front RS frame mounts used simple brackets to hold the front of the engine.

It also used a light weight hydraulic Mountain Bike rear break with a thumb operated master cylinder on the left handle bar, very clever.

<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=287185&d=1378188474" width="280px"/><img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=282696&d=1368344197" width="280px"/><img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=282698&d=1368344205" width="280px"/><img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=282695&d=1368344194" width="280px"/>

[F5 Dave]

Yes chop that top mount off. Here's my RG/RS with one front & one rear mount. You can see where the frame comes forward at the back but there is room to spare on the 50, but the shock is close to the top of the carb & carb to the cases.

[husaberg]

Well I sidestepped the shock problem with the Case reed conversion (as long as the carb isn't too tall). Only problem is you need a smaller carb than the KX & ideally downdraft like the RGV Mikuni. FCRs are huoooge 'case they don't care about minimising the area under the carb on a foul stroke.


Yes chop that top mount off. Here's my RG/RS with one front & one rear mount. You can see where the frame comes forward at the back but there is room to spare on the 50, but the shock is close to the top of the carb & carb to the cases.

Grumph mentioned these a while Back i hadn't seen them.
Mikuni TDMR
This one is 32mm obvious for a Foul stroke but i guess they can be made to work.as lots of the Mikuni stuff is interchangable
http://www.j-mart.biz/j-parts/images/takegawa/03-05-0041_2.jpg

It looks like Mikuni do a 34mm version of the BN pumper off the jet skis.$147 US new here (http://www.amazon.com/Mikuni-Super-Series-Carburetor-BN34-28-8010/dp/B000GV0OEK)
Which i am sure is what my mate had on his MB100.
http://ecx.images-amazon.com/images/I/41k5BA7Zv1L._SX385_.jpg

[2T Institute]

Put a throttle body on it, don't bother with the carb. Throttle body much more compact.

The F9 is losing it's EFI, a backwards step. Seems it's not in the "spirit of the era" if I want to keep racing it in VMX. Fair enough, we will teach them ( VMX pre 75 ) a lesson in how to hot up a rotary valve engine even with a carb on it. Out to the pattern shop to make up a new barrel with modern porting, eye ports etc. More than one way to skin a cat, apparently.
I'll show them " spirit of the era"!!




i don't see the need to make a complete cylinder the bighorn cylinder will modify quite nicely. What your bike desparately needs is a good pipe ....................and some proper shocks :2thumbsup

[Yow Ling]

Hey Dave would one of these do the job ?

287621

[husaberg]

Hey Dave would one of these do the job ?

287621

shhhh........Just don't Tell Dave who owns Keihin (or Showa for that matter......)

[F5 Dave]

I'd love to try one for size, perhaps when I'm down for the BoB. If you south islanders are still talking to me after I win the race;).

[Yow Ling]

I'd love to try one for size, perhaps when I'm down for the BoB. If you south islanders are still talking to me after I win the race;).

Its a pretty long race for a go kart bike

[F5 Dave]

And for this old man too. But will make victory all the sweeter:innocent:

[Flettner]

Lozza, shocks are sorted ( I hope, I've ordered some off Walter, yss ). Yes a new pipe would be good just need time to sit down and build one. Wobbly will help. Barrel, well the original will do ( for now ) with some work. Remember it's not too far off the original ( older pre 1972, 33 HP engine ) cylinder so there is a lot more to be had. But I do want to cast a new " special " one, you know " spirit of the era " and all that, teach them to not recognize EFI as sporting.:innocent:
After talking to Walter it is interesting as to how many others are ( in my class ) using supposed illegal suspension parts, the difference was I told everyone what I was up to.
Also got a young rider for the F9 this year so no more problems with an old slow operator.
It's a real shame, I'm going to have to find all my old carburetor stuff, you know, needles and jets and things and all that messy fuel every time I change it. I am leaving the variable valve in though.

[2T Institute]

Lozza, shocks are sorted ( I hope, I've ordered some off Walter, yss ). Yes a new pipe would be good just need time to sit down and build one. Wobbly will help. Barrel, well the original will do ( for now ) with some work. Remember it's not too far off the original ( older pre 1972, 33 HP engine ) cylinder so there is a lot more to be had. But I do want to cast a new " special " one, you know " spirit of the era " and all that, teach them to not recognize EFI as sporting.:innocent:
After talking to Walter it is interesting as to how many others are ( in my class ) using supposed illegal suspension parts, the difference was I told everyone what I was up to.
Also got a young rider for the F9 this year so no more problems with an old slow operator.
It's a real shame, I'm going to have to find all my old carburetor stuff, you know, needles and jets and things and all that messy fuel every time I change it. I am leaving the variable valve in though.

The rolling green hills that your race on can probably handle more HP than the goat tracks we ride on. The orginal cylinder is good enough, you don't need a new cylinder................so that free's you up to make a F9 dry clutch for me :laugh: 50hp would be easy, then the brake problems will start :msn-wink: Big advantage of a new cylinder would be a nicasil coating and no liner
Needles and jets I could get you close with a 36mm Mikuni but I would still try proper pipe first. I'll email you my 400 pipe specs.

[Flettner]

Thank you Lozza, I would appreciate that. Just rung Walter, he said shocks should be here tomorrow or perhaps Monday, can't wait! Yes the clutch on the F9 is a bit on the small side. I use plates out of a 97 KX 125 (I think) and stiff springs. Clutch actuation is by a lever arm now as the plastic spiral thing is just rubbish, is now and was also in 1973.
Dry clutch? I assume for road use?

[TZ350]

287644

Well got the old girl hooked up again but just could not get the Beast to start, plenty of fuel going back to the tank so I guess the pumps working and there is spark and some small amount of fuel blowing out the Ball Valve inlet, wouldn't fire even with a puff of either, so flooded maybe???

This and some other things puzzle me, and when I find the answer I will post it in the EFI thread.

287645

Puzzle number 1, why does injector 2 show some activity first and not injector 1.

287648 287649

The setup came with only injector 1 in the fuel calibration screen but I know where to find injector 2 (Val_Qstat2) and add it to the mix, but now, how to save it so I can see it in the calibration screen????

287646 287647

Because when I go looking for it to enter its capacity, I can see injector 1 (Val_Qstat) but I cant find number 2 (Val_Qstat2)???

Well I guess its par for the course when learning something new.

[SwePatrick]

Keep in mind,, it´s EXTREMELY easy to flood an injected engine when first trying to map an EMS to start for 1st time.
As you often got throttle closed and haven´t got a clue how much fuel it needs.

I have setup a couple of racingmachines with haltech etc etc(4 stroke)
and what i learned to make it fire for the first time.
No fuel, open throttle a small amount.
then ramp up fuel from zero to when it ignites, try to get it to run with this throttleopening at first.

then when it´s steady at say 2000rpm with that very throttleopening.
Give it some throttle upwards and downwards and listen to engine, more or less fuel?
then try new areas, you will get a 'fingerprint' of what it needs.
shut engine off.
Fill in your values in complete map, let engine cool off, then start over.
actually, you might want to wait to the next day for a complete coldstart again.

And,, as a warning ;)
You will spend hours and hours testing,mapping,fiddeling,swearing,testing,mapping ,fiddeling etc etc etc etc.....
But,, good luck!
It´s very fun and you´ll learn a lot! :)

[TZ350]

... it´s EXTREMELY easy to flood an injected engine when first trying to map an EMS to start for 1st time. ... what i learned to make it fire for the first time. No fuel, open throttle a small amount.then ramp up fuel from zero to when it ignites, try to get it to run with this throttleopening at first.

Thanks SwePatrick .... I will have another go at starting it when I have plenty of time to just quietly play with it.

[speedpro]

If you think it might be flooded just pull the plugs off the injectors and turn it. The 4-stroke Ecotron system tips in huge amounts of fuel at startup. There's a few variables that are dependant on start temp and then time after start but it's entirely possible that 15X the normal fuel amount is being injected at start and for around 5 seconds and then ramping down.

[TZ350]

If you think it might be flooded just pull the plugs off the injectors and turn it.

Good tip, thanks.


The 4-stroke Ecotron system tips in huge amounts of fuel at startup. There's a few variables that are dependant on start temp and then time after start

Yes I know where those variables are and I will have a play with them.


it's entirely possible that 15X the normal fuel amount is being injected at start and for around 5 seconds and then ramping down.

I think this is what has happened.

[TZ350]

Anyway I have found how to adjust injector 2

287685 287684

The first injector can be found under calibrations for fuel

287680 287681

The second injector is found under advanced calibration and you have to select it from the left side and add it to the right.

287682 287683

When its on the right side you select it, press OK and then you can change its value by double clicking it, editing then pressing enter to save.

[Bert]

Man, looking forward to this develop progressing. Keep it up TeeZee.
I've always been keen on a fuel injected bucket, so this and mikes project is very mouth watering.


North Island Series.
How about a side comp, battle of the teams (constructors championship)? ESE vs GPR vs Team Green vs team welly etc
Top two/three bikes home (points) from each team cumulated over the events.

I'll put a bottle of whiskey up (not Griff bootleg either)..

[Flettner]

TZ, are you in tomorrow? I'm up in Auckland so will visit. I'd like to have a look at ypur EFI GP if I may.

I'll bring my new cylinder for you to look at, a new concept, uniflow, but with a single piston. More port time / area than you can poke a stick through.

[TZ350]

TZ, are you in tomorrow? I'm up in Auckland so will visit. I'd like to have a look at ypur EFI GP if I may.

I'll bring my new cylinder for you to look at, a new concept, uniflow, but with a single piston. More port time / area than you can poke a stick through.

Keen to see that, I will be in at work 10-12ish what time are you expecting to be up this way? PM ed you my cell number.

[Frits Overmars]

I'll bring my new cylinder for you to look at, a new concept, uniflow, but with a single piston. More port time / area than you can poke a stick through.Now you've made me curious....

[speedpro]

Now you've made me curious....

You should pop over for a beer. We could have another "sad bastards" weekend especially for you. Flettner knows what I'm talking about. The boys all get together and compare stuff they've made/invented over beers and pizza.

[Frits Overmars]

You should pop over for a beer. We could have another "sad bastards" weekend especially for you. Flettner knows what I'm talking about. The boys all get together and compare stuff they've made/invented over beers and pizza.If it weren't such a long swim....

[F5 Dave]

Skype? .
.

[husaberg]

3 things about Honda 2 strokes i never realised.

They built a disk valve 125 tandem twin for a MX bike (seen the parallel twin MX never the Tandem)
can't find a pic sorry........
Big bang engine..... the NSR500 was not their first the MVX250 was actually a big bang (in more ways than one)
<img src="http://i77.photobucket.com/albums/j71/Drewskovitch/MVX.jpg" height="240px"/><img src="http://thumbs2.ebaystatic.com/d/l225/m/mjtJt1t3S5EaxTdni0A706A.jpg" height="240px"/><img src="http://www.xbhp.com/talkies/attachments/news/55578d1331702840-kawasaki-ninja-150rr-mvx250.jpg" height="240px"/>
the center gudgeon was heavier for balance. It was even bushed smaller and had a solid gudgeon on the later models.(After a spate of seizures)

The Honda EXP-2 ARC gubbins made it into production as the CRM250AR.

http://dwolsten.tripod.com/articles/jan97.html
http://www.motorcycle.com/manufacturer/honda/quick-take-honda-exp2-15170.html
<img src="http://www.ai-house.com/kaitori/img/bikes/crm250ar.jpg" height="240px"/><img src="http://databikes.com/imgs/a/b/h/i/l/honda__crm_250_ar_mk3_1999_5_lgw.jpg" height="240px"/><img src="http://databikes.com/imgs/a/b/h/i/l/honda__crm_250_ar_mk3_1999_4_lgw.jpg" height="240px"/>

[Drew]

3 things about Honda 2 strokes i never realised.

They built a disk valve 125 tandem twin for a MX bike (seen the parallel twin MX never the Tandem)
can't find a pic sorry........
Big bang engine..... the NSR500 was not their first the MVX250 was actually a big bang (in more ways than one) the center gudgeon was heavier for balance it was solid on the later models.
He Honda EXP-2 ARC gubbins made it into production as the CRM250ARI knew the MVX was big bang. Front two slugs fire together.

I think the NS400 runs the same, but for some reason it worked and the 250 didn't.

[husaberg]

I knew the MVX was big bang. Front two slugs fire together.

I think the NS400 runs the same, but for some reason it worked and the 250 didn't.

From what i read the solid yet similar size rear Gudgeon solved the MVX seizures. i guess they got it right by the time the NS400 came out
but the damage to the Rep of the MVX was already done.The gearbox is meant to be the same as a VT250. but the rest of it smacks of cost cutting.

[Rick 52]

Man, looking forward to this develop progressing. Keep it up TeeZee.
I've always been keen on a fuel injected bucket, so this and mikes project is very mouth watering.


North Island Series.
How about a side comp, battle of the teams (constructors championship)? ESE vs GPR vs Team Green vs team welly etc
Top two/three bikes home (points) from each team cumulated over the events.

I'll put a bottle of whiskey up (not Griff bootleg either)..


Very interesting !! I'm in but not sure about my team mates other commitments, now I'm not keen on Wiskey, could we ride for good Port ?

[seymour14]

Very interesting !! I'm in but not sure about my team mates other commitments, now I'm not keen on Wiskey, could we ride for good Port ?

Why not, a bit of gentlemanly rivalry never hurt anyone.....and Port is the poison of gentlemen.

[Drew]

From what i read the solid yet similar size rear Gudgeon solved the MVX seizures. i guess they got it right by the time the NS400 came out
but the damage to the Rep of the MVX was already done.The gearbox is meant to be the same as a VT250. but the rest of it smacks of cost cutting.
To my knowledge, there were no changes to the MVX motor the whole time it was in production. I've seen inside more of them than any person should, and they all run a larger rear gudgeon. I don't know how that would contribute to the rear slug seizing, please explain since I bought Whitetrash a running one. But lets face it, that's got a very finite number of starts before it's not a runner any more.

[TZ350]

I'm in but not sure about my team mates other commitments,

I am not sure we have enough running F4's to make it a Team race, most of our (mostly Chambers) effort at the moment is going into getting some F5 50's onto the track.

[husaberg]

To my knowledge, there were no changes to the MVX motor the whole time it was in production. I've seen inside more of them than any person should, and they all run a larger rear gudgeon. I don't know how that would contribute to the rear slug seizing, please explain since I bought Whitetrash a running one. But lets face it, that's got a very finite number of starts before it's not a runner any more.

This is the way it relayed to me.

The original was a very large gudgeon pin (say about 18mm) older and revised rear rods are all the same.
but were sleeved for the later smaller say 14mm solid pin.
The reasoning given to me was the heat transfer was not even.
Very few countries got the MVX. NZ might have only got the early model.

<img src="http://upload.wikimedia.org/wikipedia/commons/4/4b/Motorcycles-Honda-MVX250F-Conrod-Piston_01.JPG" height="210px"/><img src="http://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Motorcycles-Honda-MVX250F-Conrod-Piston_02.JPG/800px-Motorcycles-Honda-MVX250F-Conrod-Piston_02.JPG" height="210px"/><img src="http://i1101.photobucket.com/albums/g422/MBX250/IMG_0621.jpg" height="210px"/><img src="http://i1101.photobucket.com/albums/g422/MBX250/IMG_0724.jpg" height="210px"/>
Honda even went as far as listing at the last update teflon coated (Rear only) piston in 14mm pin the fronts are all 12mm rears as i have said are 18mm or 14mm for the later models.
lots of MVX stuff discussed here even a Kiwi.

http://diffrentstrokers.com/phpBB2/viewtopic.php?t=934
there were loads of pistons made for the MVX. The fiche only lists three grades of STD, but they did make >025, 0.5 & 0.75 oversize. The rears came in two pin sizes 14mm & 18mm and the last revisions 506 are teflon coated
The best advice I can give you is to to contact MVX and NSR nut, Alistair. His email address is elmarie@dsl.pipex.com Have a look at this page on his website for yet more MVXs >> http://www.elmarie.dsl.pipex.com/MVX.htm

You could try Yahoo Japan for a crank as MVX stuff comes up on there quite regularly; http://search.auctions.yahoo.co.jp/j...ale=0jp&acc=jp
After searching the globe for crankseals, I did find the original manufacturer based in the USA who was prepared to make a limited run of crankseals. the dimensions quoted were 52 mm x 36mm x 6mm Nitrile 80. The catch was they would only make a minimum of 90 pieces with a lead time of 19-20 weeks at a cost of $2.12 American dollars each. Eventually I sourced some equivalent seals in New Zealand which are very close in size which appear to be doing the job. Three donor engines have been used to source enough parts to build a good crank and find suitable combinations of barrels
There is a routing of the coolant difference as well i understand.between models


You can do all of that now - here is the electric water pump on the Pre 82 Junior - Frepin400.
Have you seen these (http://www.arf33.com/Special_Parts_New.htm) Wob?
http://www.arf33.com/arf33_special_parts/pompa%20liquido/REP-03/m_pompa_REP-03_01.jpghttp://www.arf33.com/arf33_special_parts/pompa%20liquido/REP-03/m_GIF_REP-03.gifhttp://www.arf33.com/arf33_special_parts/pompa%20liquido/m_arf33_pompa_REP-02_02.jpghttp://www.arf33.com/arf33_special_parts/pompa%20liquido/m_arf33_pompa_REP-02_01.jpg

NEW GENERATION RACING ELECTRIC PUMP
RACING ELECTRIC PUMP REP-01
Description: 9-15v, 20mm tube, 800-1000lt/h flow, consumption 0,95Ah, Weight 265gr
85€
RACING ELECTRIC PUMP REP-02
Description: 9-15v, 20mm tube, 800-1000lt/h flow, consumption 1,05Ah, Weight 350gr
55€

Bellow attached is the Official story of the MVX revisions from Honda

[Drew]

This is the way it relayed to me.
The original was a very large gudgeon pin (say about 18mm) older and revised rear rods are all the same.
but were sleeved for the later smaller say 14mm solid pin.
The reasoning given to me was the heat transfer was not even.
Very few countries got the MVX. NZ might have only got the early model.

That's at odds with what we found when researching how to make them reliable. No one seems to have achieved it with regularity.

There's not even a clear reason as to why they seize up the rear pot. People think they get too hot, but battering the cooling doesn't help.

[TZ350]

We could have another "sad bastards" weekend, Flettner knows what I'm talking about.

While Flettner was there Kel dropped by to talk with Chambers and Speedpro turned up and gave me a few tips on the EFI.

So we had a sortof sad bastards hour or so, where Flettner showed us his new cylinder idea, and now I have thrown my hat in the ring for a 100cc H2O version. But not sure if its going to be coupled to a CVT or traditional gears yet.

287774

I hadn't immediately registered it the other night but the EFI TPS (top right corner) on the ProCal monitor screen has stoped working, it is stuck on 18% and not registering changes in throttle position.

The Ignitec is still registering the TPS OK so the conclusion is that its an Ecotrons software problem and Speedpro said he had seen this issue talked about on the Kawasaki 250 Ninja forum.

http://www.ninjette.org/forums/showthread.php?t=96942&highlight=ecotrons&page=42

And the answer on the forum was to un-install the Ecotrons ProCal program and reload it. It makes sense that the EFI firmware is probably OK and its only the monitor part of the calibration software on the laptop that has become corrupted.

I guess there will be a series of small issues like this to work through before the Beast is up and barking again.

[Grumph]

To my knowledge, there were no changes to the MVX motor the whole time it was in production. I've seen inside more of them than any person should, and they all run a larger rear gudgeon. I don't know how that would contribute to the rear slug seizing, please explain since I bought Whitetrash a running one. But lets face it, that's got a very finite number of starts before it's not a runner any more.

If the other cylinders aren't prone to seizure but the one with the heavy gudgeon is...that's the cause. I'd pick that the extra weight causes more side load on the piston which makes it hard for the oil film to say the least.

It would be interesting - and not hard - to build one up with 3 identical rods and rebalance the crank. Plenty of webs to take weight off to achieve the desired 100% of one side of the Vee balance factor.

[2T Institute]

3 things about Honda 2 strokes i never realised.

They built a disk valve 125 tandem twin for a MX bike (seen the parallel twin MX never the Tandem)
can't find a pic sorry........
Big bang engine..... the NSR500 was not their first the MVX250 was actually a big bang (in more ways than one)

Often thought about getting a MVX engine and bolting on 3 CR 85 cylinders, with an ignition and pipes would make a awesome roadie in a decent frame. The cycle parts were complete shit, as a L plater the choice was clear, shitter MVX, the KR 250 with those weird spinning discs, a cheap and cheerful RZ or the race replica RG. We all wanted the RG but could only afford the RZ, the KR was probably the best bike.

Gilera made a tandem twin 125 mxer, I know of only 1 disc valve honda that was a 125 mxer raced in the All Japan mx championship only (it's not at the Collection Hall), Honda did make a RC125M twin mxer (with RIBI front end) but that was a reed valve. That bike is featured in VMX mag No26.


http://i155.photobucket.com/albums/s297/Lozza85_2007/30_1024.jpg (http://s155.photobucket.com/user/Lozza85_2007/media/30_1024.jpg.html)

http://p.vitalmx.com/photos/forums/2013/03/22/honda_rc125m_669581.jpg

http://www.mxworksbike.com/Gilera_twin_2_750.jpg
http://www.mxworksbike.com/Gilera_twin_1_750.jpg

The RSA-before-there-was-a-RSA CZ125 circa late 80's
http://i155.photobucket.com/albums/s297/Lozza85_2007/519_ProtoRH.jpg (http://s155.photobucket.com/user/Lozza85_2007/media/519_ProtoRH.jpg.html)

[seymour14]

[QUOTE=2T Institute;1130615412]Often thought about getting a MVX engine and bolting on 3 CR 85 cylinders, with an ignition and pipes would make a awesome roadie in a decent frame. The cycle parts were complete shit, as a L plater the choice was clear, shitter MVX, the KR 250 with those weird spinning discs, a cheap and cheerful RZ or the race replica RG. We all wanted the RG but could only afford the RZ, the KR was probably the best bike.

Got one of those ferreted away for a rainy day, I see KR's are banned as learner bikes now! That's a bit stink, she was a spirited bike to ride.

[mr bucketracer]

[QUOTE=2T Institute;1130615412]Often thought about getting a MVX engine and bolting on 3 CR 85 cylinders, with an ignition and pipes would make a awesome roadie in a decent frame. The cycle parts were complete shit, as a L plater the choice was clear, shitter MVX, the KR 250 with those weird spinning discs, a cheap and cheerful RZ or the race replica RG. We all wanted the RG but could only afford the RZ, the KR was probably the best bike.

Got one of those ferreted away for a rainy day, I see KR's are banned as learner bikes now! That's a bit stink, she was a spirited bike to ride.so how did you get a pic of david bain with the bike?

[husaberg]

Berts TZR100 Sleeve was a slipping from memory.....


Some of Jans collaborations
Jamathi, Piovaticci, Bultaco, Minarelli, Garelli, Rumi, Schuurman, Aprilia, Derbi..

Oh i missed Cagiva too, not surprised he was there........ but don't often see it mentioned?


If the other cylinders aren't prone to seizure but the one with the heavy gudgeon is...that's the cause. I'd pick that the extra weight causes more side load on the piston which makes it hard for the oil film to say the least.

It would be interesting - and not hard - to build one up with 3 identical rods and rebalance the crank. Plenty of webs to take weight off to achieve the desired 100% of one side of the Vee balance factor.
it is in the Text i posted as an attachment exactly what you mention but the rebalancing the crank would be a great idea they changed the coolent routing as well but i have passed that direct to Drew.


Often thought about getting a MVX engine and bolting on 3 CR 85 cylinders, with an ignition and pipes would make a awesome roadie in a decent frame. The cycle parts were complete shit, as a L plater the choice was clear, shitter MVX, the KR 250 with those weird spinning discs, a cheap and cheerful RZ or the race replica RG. We all wanted the RG but could only afford the RZ, the KR was probably the best bike.

Gilera made a tandem twin 125 mxer, I know of only 1 disc valve honda that was a 125 mxer raced in the All Japan mx championship only (it's not at the Collection Hall), Honda did make a RC125M twin mxer (with RIBI front end) but that was a reed valve. That bike is featured in VMX mag No26.


<img src="http://s155.photobucket.com/user/Lozza85_2007/media/30_1024.jpg.html" height="200px"/><img src="http://i155.photobucket.com/albums/s297/Lozza85_2007/30_1024.jpg" height="200px"/><img src="http://p.vitalmx.com/photos/forums/2013/03/22/honda_rc125m_669581.jpg" height="200px"/><img src="http://www.mxworksbike.com/Gilera_twin_2_750.jpg" height="200px"/><img src="http://www.mxworksbike.com/Gilera_twin_1_750.jpg" height="200px"/>

The RSA-before-there-was-a-RSA CZ125 circa late 80's
<img src="http://s155.photobucket.com/user/Lozza85_2007/media/519_ProtoRH.jpg.html" height="240px"/><img src="http://i155.photobucket.com/albums/s297/Lozza85_2007/519_ProtoRH.jpg" height="240px"/>

Must show you how to resize pics Lozza:bleh:
The twin i referred to was def an tandem rather than a parallel it was abandoned when it was no faster where it counts on the track.
Lots of Stuff Honda did were not seen by the public although they were great and storing their stuff.
The engineer in charge of the MX twin project i refered to was Shinichi Miyakoshi, he likely did both of the ones you mentioned as well(Cause he was their MX go to guy)as well as later doing the RS500 (Design engineer in charge)
Maybe you could contact him he is likely on FB

[husaberg]

Now that is a laugh. Even I could extract 40 HP from a blown 100 cc fourstroke. And a really dedicated foulstroketuner could make it 50. "But no competition engines" :facepalm:.



I shouldn't post this here for fear of being burnt at the stake.But geeze i never knew that Honda managed to squeeze so much at their first attempt.

Also added the Fuel injection stuff, as it looks like Dave could have been right. (about the DI ban) although i think it may have actually been a fuel pressure above 10 bar ban. (Plus he was wrong about most everything else)

[Flettner]

http://i1056.photobucket.com/albums/t380/uniflow/IMG_1257_zpsae1acc20.jpg
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1256_zps74f40053.jpg
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1258_zps5e0e3437.jpg
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1260_zps7582374f.jpg

Just some random shots of uniflow cores and castings, this one is a 650cc
The cores are exhaust port and water cooling ( on the exhaust side ).

[speedpro]

I shouldn't post this here for fear of being burnt at the stake.But geeze i never knew that Honda managed to squeeze so much at their first attempt.

So I should be looking at 75hp, minus a bit because my motor "only" has 4 valves /cylinder, say 60hp, minus a bit because it only revs to 18,500rpm, say 50hp. Nooooo sweat. With alcohol and nitro maybe, for about a second.

[husaberg]

So I should be looking at 75hp, minus a bit because my motor "only" has 4 valves /cylinder, say 60hp, minus a bit because it only revs to 18,500rpm, say 50hp. Nooooo sweat. With alcohol and nitro maybe, for about a second.

They were on Carbs too, so maybe no Intercooling either......my initial calc i did, before i knew what they got, was up to 45hp for a 100cc 4 valve twin intercooled with a half speed 300 cc rootes blower on Avgas with water injection. I couldn't find any forged dished pistons though in a suitable size. I hope you can.
I am guess the Honda's fuel owed a bit to F1, probably mostly toluene. Remember the life for a F1 qualifying engine was about 8 minutes.

[TZ350]

http://i1056.photobucket.com/albums/t380/uniflow/IMG_1256_zps74f40053.jpg

Just some random shots of uniflow cores and castings,

Pattern making is a special art, and I would love to see more shots of how you go about making patterns, especially the ones for your new uni flow engine.

[TZ350]

I would love to see much more of Flettners patten making techniques.

287858

Meanwhile I still have the software problem.

I came into work early so I could remove then re load the ProCal software but that didn't fix the problem.

287859

But the Oscilloscope screen shows the TPS functioning OK. So thankfully it looks like only a glitch in the Gauge screen.

The Oscilloscope screen is great because you can select any number of variables and display and record them in real time as the motor is running.

[F5 Dave]

I shouldn't post this here for fear of being burnt at the stake.But geeze i never knew that Honda managed to squeeze so much at their first attempt.

Also added the Fuel injection stuff, as it looks like Dave could have been right. (about the DI ban) although i think it may have actually been a fuel pressure above 10 bar ban. (Plus he was wrong about most everything else)
So what you are saying is that I was right but it burns you so bad you need a throw away line claiming that I am wrong. I think you've been breathing the same fumes that Tackeo Fukui was inhaling when he stuttered (from that article posted) : "The turbo twin is easy to start, just like a 2 stroke but sounds much better"

C'mon! sheesh. No accounting for taste really is there?

[husaberg]

So what you are saying is that I was right but it burns you so bad you need a throw away line claiming that I am wrong. I think you've been breathing the same fumes that Tackeo Fukui was inhaling when he stuttered (from that article posted) : "The turbo twin is easy to start, just like a 2 stroke but sounds much better"

C'mon! sheesh. No accounting for taste really is there?

no........no......no.... And no idea.
I prefer the sound of the Triple myself

http://www.youtube.com/watch?v=uLUex1BssgY

[2T Institute]

Fukui-san went on to run the NR750 endurance racer project and eventualy became CEO of Honda( very odd by western standards to have a CEO that has the slightest idea of technical aspects of the products that company makes) he was in charge when the GFC hit and F1 program was culled but MotoGP stayed on, would like to think that was because he was a 'bike bloke'

[F5 Dave]

. . . eventualy became CEO of Honda( very odd by western standards to have a CEO that has the slightest idea of technical aspects of the products that company makes) . . '

Or the salesmen. Sorry one of those days.

[wobbly]

Seems my Czech speaking pipe building friend has poked the ECU wasp nest with a stick.
A very large box of Ignitech units is in the air over the Pacific as we speak.
Hold onto your buckets,fuel injection is looming.

[F5 Dave]

Good to hear its working out. Good timing I think I've almost poked enough aside for another P4 for the 50.

[husaberg]

Fukui-san went on to run the NR750 endurance racer project and eventualy became CEO of Honda( very odd by western standards to have a CEO that has the slightest idea of technical aspects of the products that company makes) he was in charge when the GFC hit and F1 program was culled but MotoGP stayed on, would like to think that was because he was a 'bike bloke'


Or the salesmen. Sorry one of those days.

Anyway some pics of the RS500 Honda one of the cleverestly simple engines ever made....
Not sure what the Top Chassis is but i like it.
People often over look that before Yamaha made the engines in near works spec available for ROC and Harris.
Honda sold the NS500
These bikes other than less Mag and CF and about 5 less HP Were virtual works Replica's.

I was kind of hoping Wob would have chipped in by now with the firing order and crank design of the BSL i guess it was much more MVX250 than RS500 only balanced with the crankshaft rather than the pistons?


<img src="http://www.google.co.nz/url?source=imglanding&ct=img&q=http://www.motocykl-online.cz/img/galery/motocykly-honda-rs-500-r_2.JPG&sa=X&ei=dIxCUumsFYnilAXW-YHYCA&ved=0CAkQ8wc&usg=AFQjCNErDT-tXsXdd68zdM8VN24IwVWiKQ" height="640px"/>
<img src="http://farm9.staticflickr.com/8281/7755266018_a7b5004105.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8435/7755267680_c11e5fbdf6.jpg" height="405px"/>
<img src="http://farm8.staticflickr.com/7113/7755267134_01a47f2915.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8286/7755266728_5d0d02f16e.jpg" height="405px"/>
<img src="http://farm9.staticflickr.com/8436/7755262482_fe0301e826.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8448/7755265504_838551d5aa.jpg" height="405px"/>
<img src="http://farm9.staticflickr.com/8434/7755268734_f984ff4c71.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8287/7755268182_f05c4f0c95.jpg" height="405px"/>
<img src="http://farm8.staticflickr.com/7246/7755257306_720436a045.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8448/7755265504_838551d5aa.jpg" height="405px"/>
<img src="http://farm8.staticflickr.com/7270/7755258942_315520dc0e.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8281/7755254216_385aef94df.jpg" height="405px"/>
<img src="http://farm8.staticflickr.com/7131/7755264934_4a8798ebd3.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8425/7755264148_635ebe0f0c.jpg" height="405px"/>
<img src="http://farm9.staticflickr.com/8425/7755263316_4d71cecc20.jpg" height="517px"/><img src="http://farm8.staticflickr.com/7111/7755253482_4d6e76e4fc.jpg" height="517px"/>
<img src="http://farm8.staticflickr.com/7263/7755260660_e105464e51.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8305/7755259844_a67b2ca0b4.jpg" height="405px"/>
<img src="http://farm8.staticflickr.com/7246/7755258098_6e655754a6.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8285/7755252566_fbb18559bc.jpg" height="405px"/>
<img src="http://farm9.staticflickr.com/8296/7755255598_54a141486d.jpg" height="405px"/><img src="http://farm9.staticflickr.com/8292/7755254806_36149660ec.jpg" height="405px"/>
<img src="http://sphotos-a.xx.fbcdn.net/hphotos-frc1/p480x480/554698_479989055353647_1953501054_n.jpg" height="430px"/><img src="https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-ash4/406348_464283983590821_1781037739_n.jpg" height="430px"/>
<img src="https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-ash4/424348_473341909351695_650280617_n.jpg" height="540px"/>

<img src="http://www.deejay51.com/HONDA%20HALL/HONDAHALL%20NS500D.JPG" height="399px"/><img src="http://www.deejay51.com/HONDA%20HALL/HONDAHALL%20NS500A.JPG" height="399px"/>

[SwePatrick]

*drooool* ;)

however, this leads me to a question.
This picture:
http://farm9.staticflickr.com/8305/7755259844_a67b2ca0b4.jpg

It´s a cutaway in the pistonskirt.
Have anyone tested and documented any gain/losses with this?

I´m about to test it on my little honda projekt.

And by the way, that reedvalve that you posted Wobbly..
that one really kicks ass. i made a copy and slotted in this one instead of my v-force 2.
And,, goddamn!!! no dyno yet.
but with superlative: GODDAMN v-force can just stay in the shelf!!! nice to look at,, but no more.
I asked earlier about pipe pressure, and now with this reed the engine is totally insane.
Pipe pressure went up from 0.2bar to 0.45-0.5bar, no good ofcourse.
But it must mean the engine produces more exhaustmass = power!
I will dyno as soon as i sorted the carb problem i´m fighting at the point.
It sucks the floatbowl dry *lol*, never done this before.
I´ve got an Mikuni TMXX carb 39.5mm(bored out 38mm) and those are sensitive with floater height.
So i have ordered a Keihin PWM40 with powerjet.

Now when that is sorted i will sort out the pipe pressure and then dyno again.

Thanks Wobbly, really Thanks sincerely(spelling)

Best regards
Patrick
Sweden.

[10bikekid]

I shouldn't post this here for fear of being burnt at the stake.But geeze i never knew that Honda managed to squeeze so much at their first attempt.

Also added the Fuel injection stuff, as it looks like Dave could have been right. (about the DI ban) although i think it may have actually been a fuel pressure above 10 bar ban. (Plus he was wrong about most everything else)

Remember reading that someone (maybe Fast Freddie) said the Honda 250 turbo was near unridable as it had ziltch low end and then a mad top end rush (coming from Fredie that would have been high praise)

[wobbly]

I didnt know you wanted me to tell re balance and firing pattern of the BSL.
A young engineer Simon Longdill working with me on the project wrote a balance program for his BE thesis and we tried every variation known to man.
One night I dreamed wierdly that maybe we should try firing two cylinders together.
We tried the middle and RH cylinder and middle running as a concurrent twin, with the 120* cylinder angle and firing the LH cylinder 120* later.
Making in effect a big bang firing order.
Each cylinder was balanced at 58% and a balance shaft ran across the back from a gear between the mid and RH pair, this then drove the clutch.
This setup of course makes it run "backwards" and we spent alot of time analysing the effects of gyro precession on the handling.
The two cylinders firing together gave perfect primary balance with only constant eccentric loads on the roller mains, that of course they are well designed for.
This layout resulted in a vibration free tripple, but the torsional crank harmonics caused endless issues with breaking off the integral big end pins.
Big radi and shot peening didnt fix the problem,but it was finally solved in the short term by boring the wheels and using a normal press fit on both sides.
It really needed a case redesign and 5mm added to the 3 wheels that would have made no difference to anything with a slightly wider engine.
At the time I was obsessed with the narrowest and shortest package possible - a good design approach, but flawed in the final execution.

[husaberg]

I didnt know you wanted me to tell re balance and firing pattern of the BSL.
A young engineer Simon Longdill working with me on the project wrote a balance program for his BE thesis and we tried every variation known to man.
One night I dreamed wierdly that maybe we should try firing two cylinders together.
We tried the middle and RH cylinder and middle running as a concurrent twin, with the 120* cylinder angle and firing the LH cylinder 120* later.
Making in effect a big bang firing order.
Each cylinder was balanced at 58% and a balance shaft ran across the back from a gear between the mid and RH pair, this then drove the clutch.
This setup of course makes it run "backwards" and we spent alot of time analysing the effects of gyro precession on the handling.
The two cylinders firing together gave perfect primary balance with only constant eccentric loads on the roller mains, that of course they are well designed for.
This layout resulted in a vibration free tripple, but the torsional crank harmonics caused endless issues with breaking off the integral big end pins.
Big radi and shot peening didnt fix the problem,but it was finally solved in the short term by boring the wheels and using a normal press fit on both sides.
It really needed a case redesign and 5mm added to the 3 wheels that would have made no difference to anything with a slightly wider engine.
At the time I was obsessed with the narrowest and shortest package possible - a good design approach, but flawed in the final execution.

Thanks when I got to thinking when I read this recently (including esp the bit i already posted), the other day and i assume the NS400 was the same set up as well.
Its a shame Honda never realised what they were potentially onto, (with the set up on the MVX.)
just maybe, they should have balanced it with the crankweight's (as Greg said) rather than the piston pin. and it could have been even smoother and even easier on tyres, which was its advantage rather than weight.
I say this as I read somewhere else as well they would have kept developing the RS500/NS500 but were concerned about the vibration had already made the chassis heavier to cope with vibes and hadn't fully developed the engine further because of it.

*Please Note the cankseals on the DKW3

[F5 Dave]

And because they couldn't help themselves, more power is always better, cue a V4 & find riders that don't bitch too much that it doesn't go around corners (Lawson was a bad choice there).

[wobbly]

A good story to relate was when the BSL was first started at Philip Island.
We opened the pit door to find about 100 people waiting to see it.
It was started and I was hanging onto the throttle , blipping it to warm up.
King Kenny strode forward with his Team Roberts entourage in tow.He grabbed hold of the foot peg as i gave it a good rev.
Turning around to the team he said real loud, as he does " these cunts know more about engine balance than any of you fuckers " patted me on the back
with a wink and walked away.
Later in their pit I got to do the same thing - and it was scary how much the buzzing vibration actually hurt your hand.
Yes - I did ask for a job, but they had already contracted the NS500 designer to draw a new engine.

[Grumph]

A good story to relate was when the BSL was first started at Philip Island.
We opened the pit door to find about 100 people waiting to see it.
It was started and I was hanging onto the throttle , blipping it to warm up.
King Kenny strode forward with his Team Roberts entourage in tow.He grabbed hold of the foot peg as i gave it a good rev.
Turning around to the team he said real loud, as he does " these cunts know more about engine balance than any of you fuckers " patted me on the back
with a wink and walked away.
Later in their pit I got to do the same thing - and it was scary how much the buzzing vibration actually hurt your hand.
Yes - I did ask for a job, but they had already contracted the NS500 designer to draw a new engine.

If you were doing a similar triple now, we could assume injection would be an integral part of the package....This would let you close up the Vee angle as there's less to accomodate in there. Maybe cut it down to 90 degrees - which brings good things like no balance shaft and much easier primary balance...

Guzzi got around a 120 degree twin by having both cylinders reach TDC at the same time with offset pins. That balances up much more like a flat twin. Pretty smooth reportedly.

[F5 Dave]

Carb boring
Ok throwing this out to the panel: Maybe carbs are boring with all this FI talk, but here's my quandary; My planned move to the Solenoid PWK has fallen foul of a large stout bit of ally in the way (the RS frame). So my next plan is to retrofit a solenoid PJ to my downdraft RGV carb. In the process I was keen to go bigger.


it appears the VJ21 & 22 carb bodies are the same just bored bigger. Indeed I've seen RG150 carbs are the same body offset a crazy amount to 26mm. The slide lends itself to this modular approach.

So on the face of it it looks like I could offset bore the 32mm carb to 34mm & end up with a central bore as it it were made that way. I've read about people taking them out to 35.8 so another tickle to 35mm would seem attractive. As luck has it I have a spare carb body missing floats/bowl etc.

But the question really revolves around the emulsion tube shroud that would obviously get taken out in the process.

Unlike the old days, the emulsion tube does not have this shroud (and the screw in design & size makes it infeasible), it is incorporated in ally carb floor & quite large. I'm scared of making one & gluing it in place as it it became detached it would enter the engine. It is hard to machine a decent 'key' for it to wedge into.

[richban]

Carb boring
Ok throwing this out to the panel: Maybe carbs are boring with all this FI talk, but here's my quandary; My planned move to the Solenoid PWK has fallen foul of a large stout bit of ally in the way (the RS frame). So my next plan is to retrofit a solenoid PJ to my downdraft RGV carb. In the process I was keen to go bigger.


it appears the VJ21 & 22 carb bodies are the same just bored bigger. Indeed I've seen RG150 carbs are the same body offset a crazy amount to 26mm. The slide lends itself to this modular approach.

So on the face of it it looks like I could offset bore the 32mm carb to 34mm & end up with a central bore as it it were made that way. I've read about people taking them out to 35.8 so another tickle to 35mm would seem attractive. As luck has it I have a spare carb body missing floats/bowl etc.

But the question really revolves around the emulsion tube shroud that would obviously get taken out in the process.

Unlike the old days, the emulsion tube does not have this shroud (and the screw in design & size makes it infeasible), it is incorporated in ally carb floor & quite large. I'm scared of making one & gluing it in place as it it became detached it would enter the engine. It is hard to machine a decent 'key' for it to wedge into.



I asked the same question about my 30mm Japanese import rgv carbs of my bro. 32H 28W. He suggested a D shape dia grinder mission. In the end I just brought some 34's of ebay for 90 squid. Problem solved, for now. But really after seeing your bike run the other day you should leave it the hell alone till well after our little trip down south. After that happy to lend you a 34 for testing.

[speedpro]

Give it to Glen and have him run a slot drill or whatever around the throat but staying away from the base. You could even square it up a bit by removing the top corners a bit making the throat more of an oblong shape, with rounded corners. Probably a good reason flow wise for not doing that but it would be interesting and you could jam it on a flow bench afterwards.

[Gigglebutton]

Rob at ESE made a holder for his lathe to offset bore his carbs. The Lectron carb I use on the FXR has 2mm of taper and I think there high verbosity carbs have more taper .

[richban]

Give it to Glen and have him run a slot drill or whatever around the throat but staying away from the base. You could even square it up a bit by removing the top corners a bit making the throat more of an oblong shape, with rounded corners. Probably a good reason flow wise for not doing that but it would be interesting and you could jam it on a flow bench afterwards.

Way back when messing with a shithouse TM28 we tried adding more area with grinding out the top section of the throat. It did add more CFM on the flow bench but no where near the amount a 32mm pwk did. And the 32 fuelled better at half throttle. This in turn started my hatred towards mukuni carbs.

[F5 Dave]

I'm not keen on them, but kinda stuck for space

[ac3_snow]

This in turn started my hatred towards mukuni carbs.

Hmmm, between this, and hearing about the ease of mixture adjustment on the kart carburetors... I am beginning to think the flatslide mikuni I have sitting in the lounge isn't so flash after all.

[F5 Dave]

They can work just fine, just have to get lucky with the needle I think

[2T Institute]

A good story to relate was when the BSL was first started at Philip Island.
We opened the pit door to find about 100 people waiting to see it.
It was started and I was hanging onto the throttle , blipping it to warm up.
King Kenny strode forward with his Team Roberts entourage in tow.He grabbed hold of the foot peg as i gave it a good rev.
Turning around to the team he said real loud, as he does " these cunts know more about engine balance than any of you fuckers " patted me on the back
with a wink and walked away.
Later in their pit I got to do the same thing - and it was scary how much the buzzing vibration actually hurt your hand.
Yes - I did ask for a job, but they had already contracted the NS500 designer to draw a new engine.

A PR master is Kenny :laugh:, he actualy got 2 Japanese engineers Yoda-san and Oguma-san ex HRC and Yoda ex Yamaha(the irony) first thing they did was reduce the engine length by 50mm and that allowed a 50mm longer swingarm, which cured the chronic understeer. Then they started to get the Modenas going.

Would you go a triple again Wob or a twin 68X68.5 disc valve with twin discs like the Exactweld ?

[TZ350]

288003

http://www.sportmotor.hu/motoros_kepek/tuning/?dr=52805&cmd=pic&id=707616

Interesting series of photos of someones project where they are fitting a home made performance sleeve to their cylinder.

[wobbly]

A triple even more so now,as injection would make fitting the intake a doddle.
The weight advantage offset by the power that it is capable of making still means it is a great compromise,and it packages well with two up and one down as Honda did originally.
When you think back to McWilliams putting the Aprilia on pole at Philip Island this shows that the idea of a 250 bike with a heap of power is valid.
But the twin simply cant make enough power, and even with its weight advantage can never be the best choice for corner speed Vs straight line ability.

[richban]

A triple even more so now,as injection would make fitting the intake a doodle.
The weight advantage offset by the power that it is capable of making still means it is a great compromise,and it packages well with two up and one down as Honda did originally.
When you think back to McWilliams putting the Aprilia on pole at Philip Island this shows that the idea of a 250 bike with a heap of power is valid.
But the twin simply cant make enough power, and even with its weight advantage can never be the best choice for corner speed Vs straight line ability.

On the subject of 250's. If one had a say, a Honda MC28 engine and was wanting to make it go the best it could possible go. With head work port, pipe, carbs, ignition, What you reckon it could make at the wheel?

[F5 Dave]

Any thoughts on my emulsion tube shroud? Or rather carb body shroud?

[Ocean1]

Any thoughts on my emulsion tube shroud? Or rather carb body shroud?

Got a picture mister?

[husaberg]

Yamaha OW54

I remember TZ showing a pic of a Cagiva's inline disk many 100's of pages ago.

Here it is I wish I had the Autocourse full story
I had a little look on google as I had never seen or herd of it but came up empty.

<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=230298&d=1296327868" height="340px"/>
and someone saying the Yam was a similar set up i guess this was it.
Only on a twin crank vee set up.

<img src="http://www.2-takt.net/000angol/20bikes/02racing/500/yamaha/yzrall/Yamaha%20YZR%20500%20OW70N.jpg" height="340px"/><img src="http://www.google.co.nz/url?source=imglanding&ct=img&q=http://www2.yamaha-motor.fr/actu/IMG/jpg/1982_ow61eg.jpg&sa=X&ei=VIZGUsbcPMnilAXVk4HIDA&ved=0CAkQ8wc&usg=AFQjCNHf_a7svpZQQPmDApkYbkPYH8gsZg" height="340px"/>

Kind of Konig like only bent and contra rotating twin cranks


The Suzuki 125's that you refer to are probably the 1977 air-cooled TR100 ( XR21) , TR125 ( XR24 ), plus the watercooled disk-valve 1978 RJ100 ( XR29 ) bikes.

These are documented in the Appendices of the book "Team Suzuki" by Ray Battersby. Claimed power output is 28.6 HP @ 11250 for the TR125 and 25 HP @ 11500 for the RJ100.

So TZ350's GP125 is still king !!
I missed this i guess it is the one Lozza mentioned.
<img src="http://jfrmc.ganriki.net/xr29-2/xr29-13.jpg" height="440px"/><img src="http://jfrmc.ganriki.net/xr29-2/xr29-11.jpg" height="440px"/>
<img src="http://jfrmc.ganriki.net/xr29-2/xr29-1.jpg" height="440px"/><img src="http://jfrmc.ganriki.net/xr29-2/xr29-2.jpg" height="440px"/>
http://jfrmc.ganriki.net/xr29-2/xr29-13.jpg

[Muciek]

288003

http://www.sportmotor.hu/motoros_kepek/tuning/?dr=52805&cmd=pic&id=707616

Interesting series of photos of someones project where they are fitting a home made performance sleeve to their cylinder.

Simson engines here in europe are very popular check this projects also http://bikepics.com/members/przemas222/cylinder/ http://www.bikepics.com/members/chylo00/p13/ http://bikepics.com/members/nightfire007/p5/ , just few projects, you could find more here but language could be a barrier http://simsony.net/forumdisplay.php?f=25

[Neal]

On the subject of 250's. If one had a say, a Honda MC28 engine and was wanting to make it go the best it could possible go. With head work port, pipe, carbs, ignition, What you reckon it could make at the wheel?

At least 70hp , I had 69hp with the HRC ignition . Look for a mc21 gearbox as it has closer 4,5 & 6 gears .
Track bike or road bike ?

[husaberg]

288003

http://www.sportmotor.hu/motoros_kepek/tuning/?dr=52805&cmd=pic&id=707616

Interesting series of photos of someones project where they are fitting a home made performance sleeve to their cylinder.

might have Been sitting on this for a while.............
Guess you have seen it to......
http://forums.everything2stroke.com/threads/49513-How-It-s-Done-Projects-around-the-Shop/page3

[Forgi]

288003

http://www.sportmotor.hu/motoros_kepek/tuning/?dr=52805&cmd=pic&id=707616

Interesting series of photos of someones project where they are fitting a home made performance sleeve to their cylinder.


Hello Teezee!

It's amazing how small the world is! I personally know the owner of this moto and the cylinder as well. In my opinion it isn't a good construction at all, its STA values are also too low.
I only deal with simsons and I can tell you that such a huge cm3 (105cc) can not be made without compromise. 55 bore, 44 stroke. If you are interested in this topic just feel free to ask me!

You can find a video of the moto at this link:

http://www.sportmotor.hu/motoros_videok/simson/simson-1053mb-proba-106063

[richban]

At least 70hp , I had 69hp with the HRC ignition . Look for a mc21 gearbox as it has closer 4,5 & 6 gears .
Track bike or road bike ?

Track only. It will be in a MC21 frame. To tell you the truth I still don't know if the engine is a 21 or 28. Will have my hands on it next week.

[F5 Dave]

Got a picture mister?
Good idea. That'insert ' contains pilot drilling and no way to remove.

[Ocean1]

Good idea. That'insert ' contains pilot drilling and no way to remove.

...and if you bore it in a lathe the wee pedestal is toast.

Any reason you couldn't do it in a mill, with a long slotting drill and the carb body in a dividing head? You wouldn't get the main bore beyond the pedestal done but you could either turn it over to do the other side or just fair it in by hand with a die grinder.

[husaberg]

Anyone speak the lingo

[husaberg]

Anyone speak the lingo

The rest.....
http://teamheronsuzuki.blogspot.co.nz/search/label/Verona%20Racing%20Parts

Seen this today to.

http://www.lump-proof.com/CLASSIC/CRAFT/seel/SEEL125_2.JPGhttp://www.lump-proof.com/CLASSIC/CRAFT/seel/SEEL125_1.JPGhttp://www.lump-proof.com/CLASSIC/CRAFT/seel/SEEL125_3.JPG
http://www.lump-proof.com/CLASSIC/CRAFT/seel/

[TZ350]

Hello Teezee! It's amazing how small the world is! I personally know the owner of this moto and the cylinder as well. I can tell you that such a huge cm3 (105cc) can not be made without compromise. 55 bore, 44 stroke.

http://www.sportmotor.hu/motoros_videok/simson/simson-1053mb-proba-106063

Hi Forgi, I enjoyed the video, sounds good. I liked the photos of making the sleeve and fitting it to the cylinder because its the sort of work that I would like to do too, I hope to make my own special alloy sleeve for the Beast one day.

We are lucky to have the F4, F5 (Bucket) racing class here because it allows a whole range of different people to participate. Someone can take a stock FXR150, fit it with secondhand slicks and have a good bike while others might like to try their hand at modifying something more exotic, which is what I like to do. Our racing class rules pretty much keep everything on a level playing field and that's good.

If you have other pictures of modifying Simson engines I would love to see them posted here.

[chrisc]

A few people have asked me to share my experience with the dentist drill I purchased to use in porting two stroke cylinders.

Here is a link to the ebay auction for the item in question:
http://www.ebay.com.au/itm/Dental-Lab-Marathon-Electric-Micro-motor-N3-Contra-angle-Straight-Handpiece-/141071528551?pt=AU_Business_Industrial_Medical_Sci entific_Equipment2&hash=item20d884b267&_uhb=1

Straight head and carbine burrs work well and cut fairly nicely
Cheap
Adjustable speed
Forward and reverse option
Foot pedal
Angle head uses a different type of bit which I didn't realise when I purchased it.
The straight hand piece takes these carbine burrs: http://www.ebay.com.au/itm/10Dental-Tungsten-Carbide-Burs-2-35mm-for-Micromotor-Marathon-35-5KRPM-handpiece-/140951130991?pt=FR_JG_Beaute_Hygiene&hash=item20d157936f&_uhb=1 and I thought the angle head took the same but it actually takes these:http://www.ebay.com.au/itm/251017043168?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649.
The angle head bits are good for very detailed cutting say if you wanted to remove a millimetre off the roof of a port but not good if you wanted to take a lot of meat out the side of a port. Overall, not to happy with them for what I wanted to use them for. If I could fit the straight hand piece carbine burrs to it we'd be golden.

If you want to have a look at the other stuff this seller sells, go here: http://www.ebay.com.au/sch/m.html?_nkw=&_armrs=1&_from=&_ssn=shopvivi&rt=nc

Currently here are the tools I have below, plus a straight head Ampro die grinder which I use the two carbine burrs in photo two with. These two burrs are great and I think they're burrfect for using on the transfers and the casing but I need something to do the transfer port openings into the cylinder.

288049288048288050

So currently I'm stuck because the angle head isn't quite what I want to cut the transfer ports with and I don't really want to pay out $800+ for a CC specialty tool (http://www.ccspecialtytool.com/porting-and-polishing-2-stroke-10-cc-kit) like I probably should if I want to do the job properly/easily.

[F5 Dave]

I just used the low speed mechanical dentist head and ran it off a dremel. Works fine with diamond burrs but only as you say for 1mm subtle cuts.

[F5 Dave]

...and if you bore it in a lathe the wee pedestal is toast.

Any reason you couldn't do it in a mill, with a long slotting drill and the carb body in a dividing head? You wouldn't get the main bore beyond the pedestal done but you could either turn it over to do the other side or just fair it in by hand with a die grinder.

Hahaha, you're a GC. You're spot on. This arvo a mate came around and we looked at it and I spotted that there was an insert that with a subtle grind could slide out. Made a special tool to pull it out. Came out so easy it wasn't really required.


Didn't help much as the shroud is still part of the floor. But Matt noted that you could clamp the carb quite easily and do it on a mill. Clever bugger I sez, then turn it over and do the other side. There will be a bit that won't get reached but will be easy to dremel the thin section to match the other sides.

Thanks it was good advice and would have been super useful, takes the edge off what was going to be my clever post saying that we'd cracked it though.

[Ocean1]

Thanks it was good advice and would have been super useful, takes the edge off what was going to be my clever post saying that we'd cracked it though.

Great minds think alike, eh?

Or as one of my old tutors used to say: Son, fools never differ.

[TZ350]

A few people have asked me to share my experience with the dentist drill I purchased to use in porting two stroke cylinders.

Here is a link to the ebay auction for the item in question:
http://www.ebay.com.au/itm/Dental-Lab-Marathon-Electric-Micro-motor-N3-Contra-angle-Straight-Handpiece-/141071528551?pt=AU_Business_Industrial_Medical_Sci entific_Equipment2&hash=item20d884b267&_uhb=1


If you want to have a look at the other stuff this seller sells, go here: http://www.ebay.com.au/sch/m.html?_nkw=&_armrs=1&_from=&_ssn=shopvivi&rt=nc

I don't really want to pay out $800+ for a CC specialty tool (http://www.ccspecialtytool.com/porting-and-polishing-2-stroke-10-cc-kit) like I probably should if I want to do the job properly/easily.

Thanks ChrisC for posting that, and I had a look at your link to the CC specialty tools site too, and found an interesting page on his thoughts about porting and porting technique.

http://www.ccspecialtytool.com/2-stroke-porting-and-polishing-tips-tj

[F5 Dave]

Great minds think alike, eh?

Or as one of my old tutors used to say: Son, fools never differ.

One of the best tools in the garage is a mate to soundboard off.

I'm good at improving the idea but soso at originally.

Thanks again.

Oh yeah. Last night I was awake and wondering about the slide. I knew I'd have to trim it. But thought maybe they limited travel with different caps. Sure enough a trim will get enough travel.

[speedpro]

Or you could make a little spacer to go under the carb cap, sort of like a spacer under the barrel to lift it.

[Haufen]

If I could fit the straight hand piece carbine burrs to it we'd be golden.


You can modify them to fit the angled handpiece if the shaft diameter is the same.

[F5 Dave]

Or you could make a little spacer to go under the carb cap, sort of like a spacer under the barrel to lift it.

Nah you wouldn't bother, the slide comes up far enough to make a ~36mm lift, just the extension of the cap comes down around the cable and limits the slide.

I was thinking about thier modular design using same casting to do at least 3 carbs & thought about the slide & figured rather than have 3 slides (+ x as many alternative tune slides), instead just have three differnet length caps to limit the travel.

[Flettner]

This is a porting tool!
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1262_zps8cbdc61e.jpg
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1263_zpsaf4c99ae.jpg
http://i1056.photobucket.com/albums/t380/uniflow/IMG_1264_zpsa91cbe31.jpg

[TZ350]

That is a "Real Mans" porting tool for sure ..... :D ... very clever.

[Drew]

Should the gasket surfaces be clamped straight in the vice? I assume they are gonna get a skim if it's getting port work, but how do you measure your port timing if the heights aren't already set?

[TZ350]

Should the gasket surfaces be clamped straight in the vice?

288081

The vice is fitted with Soft Jaws, like this one and I expect it was not cranked up all that tight either, just enough to hold the job without marking it.

[F5 Dave]

Bit of space in those 350 barrels I guess. Now try a 40mm 50 barrel and still see what yer doin:lol:. Nice idea I admit.

[Flettner]

I ascertain my port timing by fairy dust and magic powder. This tool is just the wand that applies that magic ;)
Special soft, "soft jaws"
Yes I admit there is a truck load of room in the 350 barrel. A smaller version of this could be made with the smaller high speed die grinders.

[Grumph]

I ascertain my port timing by fairy dust and magic powder. This tool is just the wand that applies that magic ;)
Special soft, "soft jaws"
Yes I admit there is a truck load of room in the 350 barrel. A smaller version of this could be made with the smaller high speed die grinders.

Yes, not hard to miniaturise. Also not hard to put stops on the handle so as to cut to a defined limit.
Where did you dig that barrel up from. It lends a whole new meaning to the term "green casting"

[wobbly]

Seems perfectly reasonable Neil - to spend 500,000 on CNC gear then 50 on porting gear.
But I think the fairy dust has gone up your nose - not into the cylinder.

[Flettner]

No NO, not the fairy dust, that's what magic powder is for!
To be fair, I haven't used this tool for many years now. It's ultimately easier to cast a new cylinder with exactly what you want inside, no compromises.
I'll take a few photos of this new cylinder as I build it up ( the patterns ) if you like, you will see it's so easy everyone will be building their own cylinders soon!

[F5 Dave]

oh yeah. I'll whip some up for the van for the heck of it. Might give it some decent overtaking ompph.

[Forgi]

Hi Forgi, I enjoyed the video, sounds good. I liked the photos of making the sleeve and fitting it to the cylinder because its the sort of work that I would like to do too, I hope to make my own special alloy sleeve for the Beast one day.

We are lucky to have the F4, F5 (Bucket) racing class here because it allows a whole range of different people to participate. Someone can take a stock FXR150, fit it with secondhand slicks and have a good bike while others might like to try their hand at modifying something more exotic, which is what I like to do. Our racing class rules pretty much keep everything on a level playing field and that's good.

If you have other pictures of modifying Simson engines I would love to see them posted here.

Hi Teezee!

In Hungary there is Simson Cup or Championship, so there are a lot of tuning simsons as well.

Now I have found this link, which leads to a video of a street race, but if you are interested I can search for others, as we have races on small and huge rings.

http://www.sportmotor.hu/motoros_videok/simson/mami-kupa-simson-kat-1-futam-107529

Originally simson enginees are piston port valve enginees(inlet port), but there are some with reed valve and some rotary disc valve simsons as well. All of them are modified individually, so there aren't two which would be the same.

Here you can see some pics (membrane valve and rotary disc valve):

http://70per13.chiefyeager.fotoalbum.hu/?pageid=0

http://kepfeltoltes.hu/view/130929/106_2104_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2106_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2111_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2114_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2116_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2117_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2121_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2124_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2126_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2120_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/DSC_6646a_www.kepfeltoltes.hu_.jpg


And there is some others from www.sportmotor.hu:

http://www.sportmotor.hu/motoros_videok/simson/yamaha-yz-85-vs-simson-80-87233

http://www.sportmotor.hu/motoros_kepek/simson/?dr=67398

http://www.sportmotor.hu/motoros_kepek/simson/?dr=63946&p=1

http://www.sportmotor.hu/motoros_kepek/simson/?dr=68551&p=1

[Muciek]

Hi Teezee!

In Hungary there is Simson Cup or Championship, so there are a lot of tuning simsons as well.

Now I have found this link, which leads to a video of a street race, but if you are interested I can search for others, as we have races on small and huge rings.

http://www.sportmotor.hu/motoros_videok/simson/mami-kupa-simson-kat-1-futam-107529

Originally simson enginees are piston port valve enginees(inlet port), but there are some with reed valve and some rotary disc valve simsons as well. All of them are modified individually, so there aren't two which would be the same.

Here you can see some pics (membrane valve and rotary disc valve):

http://70per13.chiefyeager.fotoalbum.hu/?pageid=0

http://kepfeltoltes.hu/view/130929/106_2104_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2106_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2111_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2114_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2116_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2117_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2121_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2124_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2126_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/106_2120_www.kepfeltoltes.hu_.jpg
http://kepfeltoltes.hu/view/130929/DSC_6646a_www.kepfeltoltes.hu_.jpg


And there is some others from www.sportmotor.hu:

http://www.sportmotor.hu/motoros_videok/simson/yamaha-yz-85-vs-simson-80-87233

http://www.sportmotor.hu/motoros_kepek/simson/?dr=67398

http://www.sportmotor.hu/motoros_kepek/simson/?dr=63946&p=1

http://www.sportmotor.hu/motoros_kepek/simson/?dr=68551&p=1

You are not allowed there to weld the crankcases and cylinder base to get bigger transfer ports?

[husaberg]

*Please Note the cankseals on the DKW3

I guess no one did.......


<img src="http://www.southbayriders.com/forums/attachments/215313/" height="340px"/><img src="http://landbridge.net.au/Images/RG400/DKW%203503.jpg" height="340px"/><img src="http://i42.photobucket.com/albums/e336/lordcrippa/dkw-1.jpg" height="340px"/><img src="http://riviere67.free.fr/Championnes/DKW/dkw_1955_350_threecylinder_3.jpg" height="340px"/>
Teflon might be as efficient nowdays of course........
But has anyone such as Jan Frits or Wob tried?


No NO, not the fairy dust, that's what magic powder is for!
To be fair, I haven't used this tool for many years now. It's ultimately easier to cast a new cylinder with exactly what you want inside, no compromises.
I'll take a few photos of this new cylinder as I build it up ( the patterns ) if you like, you will see it's so easy everyone will be building their own cylinders soon!

Yip i reckon:innocent: but its the Crankcases i am having trouble getting my head around.
I seen your stuff on TSM very neat....

[wobbly]

We have discussed seals on here before and Lozza put me onto the non contact type that will fit such things as RS125.
The dyno certainly tells me they use alot less power than the friction prone spring loaded lip seal type.

[husaberg]

Ceramic bearings do exactly as they say - I have always used Micro Blue versions so can only speak about those.
A 50 Hp 125 will make around another 1.5 to 2 Hp with a full set, they last forever and work a treat.
In wheel bearings, a bike or kart will roll easily twice as far in neutral, after a plug chop.
Riders love not having to push back to the pit, and I love plug chops.
One thing I would like to try is to Micro Blue the surface of the sleeves where the seals run.
Seal friction is probably way bigger than the balls rolling friction, so this could be useful too.


Thanks Wob
Re seals
I am pretty sure i posted the Greeves solution to the seals a while back Std Honda Parts too.(only used on Works bikes and factory supported racer mind you.)
I can't remember what they were worth in HP.... something along the lines of 1.5-2 HP out of 30 i think. Lasted forever as well though.
This was pre admittedly Teflon days though.
Teflon ones from 2tinsitutes site he found include[/SIZE][/B]<img src="http://sharkshifter.com/zc/images/medium/man-03.jpg" height="40px"/>
HS_30 Seal crank clutch side R/H Honda 125 Carbon Teflon
Honda CR 125 right hand crank seal Carbon / Teflon 30x45x7mm low drag best seals available $10.00
HS_22 Seal crank clutch side R/H Honda CR80 / 85 Carbon Teflon
Honda cr 80/85 right hand crank seal Carbon / Teflon 22x40x7 mm low drag best seals available $10.00
HS-20 Seal Crank Ignition side L/H CR 125 & 80/85 Carbon Teflon
Seal Crank Ignition side L/H CR 125 & 80/85 Carbon Teflon 20x32x7mm best seals low drag available not legal in spec stock moto $10.00
HS-17 Seal output shaft CR 80 & 85 Honda Teflon Carbon
Honda CR 80 / 85 counter shaft seal 17x28x6mm Teflon carbon best seal available low drag $10.00
HS-26 Seal output shaft 99 CR 125 Honda Teflon Carbon
Honda CR 125 counter shaft seal 90 to 06 motors 26x37x6mm Teflon carbon best seal available low drag not spec stock legal $12.00
You can't argue with the price i guess.Cheaper than std Honda
RS125 oil seal and crankcase seals sizes attached below [/SIZE][/B]
forgive any errors it bloody late Wob.
Source they have all sorts of parts manuals and service manuals etc.
http://www.rscycles.com/pdf_partsbooks.htm
I do not part centre code 166 is CR80 the air cooled of around 1980 which shares parts with the MB5 and MB100 series.

Are the teflon seals for the RS125 kit, available in a range of sizes ie where do they come from..

Hey Wob, looks like finaly found that one thing you haven't heard about.
http://sharkshifter.com/zc/index.php?main_page=product_info&cPath=88_122&products_id=810
Most seal manufacturers can make them, seal friction is very high these make a massive difference

We have discussed seals on here before and Lozza put me onto the non contact type that will fit such things as RS125.
The dyno certainly tells me they use alot less power than the friction prone spring loaded lip seal type.
Mmm they are not available in too many sizes though.

Yamaha OW54
I remember TZ showing a pic of a Cagiva's inline disk many 100's of pages ago.
<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=230298&d=1296327868" height="140px"/>
and someone saying the Yam was a similar set up i guess this was it.
Only on a twin crank vee set up.
<img src="http://www.2-takt.net/000angol/20bikes/02racing/500/yamaha/yzrall/Yamaha%20YZR%20500%20OW70N.jpg" height="140px"/><img src="http://www.google.co.nz/url?source=imglanding&ct=img&q=http://www2.yamaha-motor.fr/actu/IMG/jpg/1982_ow61eg.jpg&sa=X&ei=VIZGUsbcPMnilAXVk4HIDA&ved=0CAkQ8wc&usg=AFQjCNHf_a7svpZQQPmDApkYbkPYH8gsZg" height="140px"/>
Kind of Konig like only bent and contra rotating twin cranks
Found these extra pics it was a little more ugly in the inlets than i imagined.
<img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/cagiva14.jpg" height="280px"/><img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/cagiva12.jpg" height="280px"/><img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/cagiva13a.jpg" height="280px"/>
<img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/rotatifs.jpg" height="280px"/><img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/rotatifs_02.jpg" height="280px"/><img src="http://www.italian.sakura.ne.jp/bad_toys/cagiva500/image/1981a.jpg" height="280px"/>

[marsheng]

250 single. I made a toroidal combustion chamber for the head. How far should the plug electrode be from the piston. Just missing it or 1/2 way between the piston and top of head chamber or other. ?


New Framewww.marshland.co.nz/ftp/MaicoBimota/Build/FramePainted.JPG

[TZ350]

250 single. I made a toroidal combustion chamber for the head. How far should the plug electrode be from the piston. Just missing it or 1/2 way between the piston and top of head chamber or other. ? New Framewww.marshland.co.nz/ftp/MaicoBimota/Build/FramePainted.JPG (http://www.marshland.co.nz/ftp/MaicoBimota/Build/FramePainted.JPG)

Hi Marsheng, I like the frame. Plug electrode gap, 6mm I think but that may only be for a 125 with a toroidal combustion chamber, you may find the answer for a 250 in the links below. If you click on the link you will find there are a few relevant posts quoted.


Here you go .....

And if you left click on a posters name then click "View Forum Posts" you can search back and find all the interesting stuff they have posted.


Ok TZ350, I kind a remember those post's, but those 6 mm are for a toroid. I wonder if the hemi is the same, thinking if the toroid brings to the flat piston the same height of the a 2mm dome piston. Thanks for your research...

[2T Institute]

Jan Thiel was due to work for Cagiva when that inline was around, despite being highly compromised Jan said that when they tested it at Mugello it was a rocket. I think Jan said Garelli came up with a offer or something, what might have been eh.

[TZ350]

Great Excitement.

288277
288286

And now........

288287

With its EFI heart beating feebly it lives, although its still on life support.

288275

Loaded the new file Matt from Ecotrons sent me to fix the Gauge display screen problem and followed a few suggestions Speedpro gave me and got the thing started and running, well more or less running anyway.

Too rich down low and lean up top, so lean it would spit back. Now I have to figure out which map is the problem and how to control when the EFI CPU switches between Load and Alpha N maps and then I can start tweeking the maps themselves.

There are other things I need to know too, like does the injection event start from the rising or falling edge of the wave form from the trigger and how do you tell the CPU how far BTDC the trigger event is and how to tell it where to end the injection event, I am just not sure how to control these yet.

Anyway its great that the thing finally works and the new computer with its serial port did the trick without crashing.

So its all looking good.....:)

[TZ350]

Page 850 link list ....


A while ago someone posted(think it was Husaberg) a link to a Swedish site with a simple program which calculates a sample of 'FOS' pipe for free. I´ve been in contact with the developer and he asked me what i would like to upgrade the program with. I said, Angels it would be nice and if it did the drawings of the different pieces so it would be easy to cut out the different parts.

link again: http://underdogsracing.com/fospipe/


What do you think guys about this http://www.dragonfly75.com/motorbike/ECtheory.html looks interesting to me.

[speedpro]

Pretty sure with Ecotrons on a 2-stroke they only use the TPS and not the MAP sensor to determine fuel at any point, + revs of course.

[Frits Overmars]

Jan Thiel was due to work for Cagiva when that inline was around, despite being highly compromised Jan said that when they tested it at Mugello it was a rocket. I think Jan said Garelli came up with a offer or something, what might have been eh.I accompanied Jan on his final visit to Cagiva; by then the inline engine had already been superseded by a square four.
The Thiel-Cagiva cooperation never happened because Angel Nieto persuaded Jan to come to Garelli instead. It resulted in six consecutive world titles for Garelli.

[Forgi]

You are not allowed there to weld the crankcases and cylinder base to get bigger transfer ports?

Yes, of course it is allowed, so if we have the chance we weld to get bigger and more appropriate B transfer passages, as it is clear that unfortunately in the original Simson cylinder there is no place for the B passage.

Wob!

We have already talked about that if we have 3 ports the best solution is to positioning the aux ports with some degrees lower than the main ports are. It was justified by Jan Thiel, especially at overrev, although I can see a lot of race cyilinders especially scooter cylinders where this is not applied. I really do not understand why this solution isn't applied by every manufacturer?

Do you have such experience with T port? As I can remember you have made T port which had higher lateral edges than the middle part of it, but it didn't work. Have you tried it with lower edges? Almost never have seen such T port even all the biggest brands apply completly flat Top Edge.

I have tried both variations but I haven't done dyno tests yet.

[2T Institute]

I accompanied Jan on his final visit to Cagiva; by then the inline engine had already been superseded by a square four.
The Thiel-Cagiva cooperation never happened because Angel Nieto persuaded Jan to come to Garelli instead. It resulted in six consecutive world titles for Garelli.

For once my memory seems vaguely reliable :lol: , got a big box of pistons handy TZ ?

[F5 Dave]

Well end of an era for me. Seems the dyno I've had access to is finally on the bunk. Don't suppose anyone has a DynoJet100 interface PC card taking up space anywhere?

[F5 Dave]

It was suggested I post a pic of it, I'm clearly overly optimistic, but desperate enough. Worse thing is, it isn't mine, but I was last to use it & then next time it didn't pick up a reading from the drum. The sensor pulses when pickup passes through, there's correct seeming voltages to the board from the PC & the other inputs (ign, button etc) seem to work. Traced the sensor track back to the 37 pin connector on the PC card so its not just broken wire.

[Sketchy_Racer]

Just as an option Dave it might be easier to go and buy a kit from performance trends datamite to retro fit to the dynojet drum. That is unless you can buy replacement dynojet parts?

[F5 Dave]

No chance of ol DJ parts I suspect. Too hard to find on ebay as all searches fouled with bike related stuff. I can't invest in the dyno as it's not mine and I have no control over it. If I can fix it cheaply I will. But even then I'm short on funds and time with 2 high demand kids.

[Drew]

No chance of ol DJ parts I suspect. Too hard to find on ebay as all searches fouled with bike related stuff. I can't invest in the dyno as it's not mine and I have no control over it. If I can fix it cheaply I will. But even then I'm short on funds and time with 2 high demand kids.But, didn't you say that you broke it?

Crosses Dave off the list of people to lend stuff to. Hehehe.

[F5 Dave]

It broke in between using it a couple of weeks apart. But I don't feel good about it. I kinda want to fix it before I have to tell the owner.

[Drew]

It broke in between using it a couple of weeks apart. But I don't feel good about it. I kinda want to fix it before I have to tell the owner.I'm just funning with ya man. Not trying to be quite as big a cunt as I usually am.

Ask Scratcha about me using his Surf some time.

[mr bucketracer]

It broke in between using it a couple of weeks apart. But I don't feel good about it. I kinda want to fix it before I have to tell the owner.i know garry from tauranga with the dyno had all the software to his old dynojet 100 -150 but know idea if he still has it .. the other thing is dyno jet did replace software for free is it failed . you just had to send the old stuff back..dont now if they still do

[Bert]

It was suggested I post a pic of it, I'm clearly overly optimistic, but desperate enough. Worse thing is, it isn't mine, but I was last to use it & then next time it didn't pick up a reading from the drum. The sensor pulses when pickup passes through, there's correct seeming voltages to the board from the PC & the other inputs (ign, button etc) seem to work. Traced the sensor track back to the 37 pin connector on the PC card so its not just broken wire.

Knowing you have likely checked it but try pulling out the board and starting up the pc then shut down and re install. Endless battles with cards from the arc keeping 70s hardware going. Some of the old cards oxidize on the pins and can drop out signals.
As Scotty suggested maybe dynojet might replace (unlikely) or performance trends (nice upgrade)..