Page 2312 of 2334 FirstFirst ... 13121812221222622302231023112312231323142322 ... LastLast
Results 34,666 to 34,680 of 35001

Thread: ESE's works engine tuner

  1. #34666
    Join Date
    7th May 2016 - 04:34
    Bike
    1980 Peugeot 103
    Location
    Colorado Springs, CO, USA
    Posts
    26
    Quote Originally Posted by lohring View Post
    By the way, how are you going to machine teacup transfers?
    Sounds like he will have the cylinder 3D printed?

  2. #34667
    Join Date
    18th May 2007 - 20:23
    Bike
    RG50 and 76 Suzuki GP125 Buckets
    Location
    Auckland
    Posts
    10,053

  3. #34668
    Join Date
    13th December 2018 - 18:06
    Bike
    1983 yamaha rd 250
    Location
    sweden
    Posts
    157
    Mantonakakis

    Yes I can see how rebuilding that crank is way fun ,ha. About that lost cylinder, look at some earlier posts. Reeds are bound to be small and the room for enlargement probably ain't great either, don't know really maybe yz80/60 is a good place to start looking. Hope the tuning goes well, and don't be concerned with the B-ports floors not aligning at bdc, is no big deal.

  4. #34669
    Join Date
    18th May 2007 - 20:23
    Bike
    RG50 and 76 Suzuki GP125 Buckets
    Location
    Auckland
    Posts
    10,053
    Quote Originally Posted by mantonakakis View Post
    One of the main restrictions will be the stock reeds, do you have the main dimensions of your RD250 reed block, or happen to know of bigger reeds to fit the 125?
    Attachment 347777
    The bolt pattern dimensions on the RD125 reed cage is essentially the same as the RD250 - 350 - 400 and RZ cages which are all much the same except the later RD and RZ cages have fiber reeds.

    Click image for larger version. 

Name:	20201124_083659.jpg 
Views:	89 
Size:	823.2 KB 
ID:	347779 Click image for larger version. 

Name:	20201124_083856.jpg 
Views:	86 
Size:	827.9 KB 
ID:	347778 Click image for larger version. 

Name:	20201124_084022.jpg 
Views:	70 
Size:	812.4 KB 
ID:	347780 Click image for larger version. 

Name:	20201124_083929.jpg 
Views:	74 
Size:	839.1 KB 
ID:	347781

    RD125 reed cage compared to a RD250/350/400 reed cage.

  5. #34670
    Join Date
    8th February 2007 - 20:42
    Bike
    TZ400
    Location
    tAURANGA
    Posts
    3,307
    Thanks everyone on the input . Seems to be too risky to have a big exhaust port sideways on , the ring will bulge outward in that direction, and even with the ring pin opposite I can see
    problems.
    All just to get rid of a header bend.
    The other thing that interests me about this project is that when I review the other engines in opposition ie up to 35cc on unleaded petrol , they all seem to be way ,way off the pace in both technology
    and Hp.
    its very easy , technically , for this engine to make 15 Hp @ 17,000 rpm - whereas it seems that many are super happy with around 8Hp.
    That is only 11.3Bar , 164 psi - bmep , very conservative in relation to many designs I have done.
    And at 17,000 + rpm as that is only 17 M/s Mean Piston Speed - again super conservative , with safe compression and completely normal ignition/combustion parameters.

    But as is the case in mini aero racing , the boaters seem all consummed with rpm , spinning them to 22,000 rpm even though the Hp peak is way back at 17,000.
    Is this something to do with prop efficiency - or some effect I am completely missing here.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Best Long Stroke.jpg 
Views:	122 
Size:	317.0 KB 
ID:	347782  
    Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.

  6. #34671
    Join Date
    7th May 2016 - 04:34
    Bike
    1980 Peugeot 103
    Location
    Colorado Springs, CO, USA
    Posts
    26
    Yeah, main issue I will face with bigger reeds is width limitation. I think the opening in the 125 cylinders is about 34mm, approximately 3mm wall thickness? Not too much room to add bigger reeds. Stock reeds are good for ~20hp according to EngMod (21mm effective diameter should be good for much more than 20hp, though? Or maybe Dat2T is converting the two reed blocks into a single effective diameter? In which case, 21mm = 20hp sounds about right).

    Just did a short highway test - If I trust the speedo, about 55mph top speed with a very strong crosswind and a big loose jacket, somewhat disappointing. Seems to run out of steam by 9k, power drops off sharply after ~8500. Runs slightly faster in 4th gear than 5th. No EGT sensor, but cylinder head temp seems in the ballpark ~320F after a minute of idling following a long climb (more than 1mile at 8-12% gradient with 50% throttle or more in 3rd gear), jetting seems in the ballpark too. My cylinders are a little out of the roundness spec, but even so I was hoping for a little better with new rings and a fresh bottom end with the stock setup. I am at 6000ft above sea level, I'll run the sim at that altitude and see if it changes the torque peak. Biggest thing I notice is that the bike does not seem to rev out as high as the stock dyno would suggest... Power band start to hit, then it drops out too soon.

    EDIT: Sim results at 6000ft vs stock dyno:
    Click image for larger version. 

Name:	altitude_Stock.PNG 
Views:	103 
Size:	41.6 KB 
ID:	347784

  7. #34672
    Join Date
    13th December 2018 - 18:06
    Bike
    1983 yamaha rd 250
    Location
    sweden
    Posts
    157
    Yes, it is tricky, considering the unfortunate long cylinder studs are also an obstacle. But welding, using putty or just grind it a little will fit something larger. One of those reeds was able to send a moped to 70 mph, whatever power that is. Flat on the tank, I remember the rd doing ~77mph stock and ~87 mph with just pipes.

  8. #34673
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    10,617
    Quote Originally Posted by mantonakakis View Post
    Did your RD lose a cylinder??
    My RD125 is running again as of yesterday, with freshly-rebuilt crank (new rods, big-end bearings and pins) and bottom end. I chose double the fun for my first attempt at a crankshaft rebuild... Time for a little tuning today, then starting work on porting and pipe plan. One of the main restrictions will be the stock reeds, do you have the main dimensions of your RD250 reed block, or happen to know of bigger reeds to fit the 125?
    Attachment 347777
    The Rd125 an the Rd200 twins have smaller reeds but the same bolt pattern. as the RD250/350/400 and many others
    Not sure if the reed cavity area is big enough for Rd250 reeds without some welding, but MX100 DT100 AG100or similar might be about, in between size. Plus are the same bolt pattern.
    if I wanted to tune a small twin maybe start with a 200. As it s bigger.
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  9. #34674
    Join Date
    28th August 2015 - 00:01
    Bike
    1975 Hodaka Wombat
    Location
    Eugene, Oregon, USA
    Posts
    230
    Quote Originally Posted by wobbly View Post
    Thanks everyone on the input . Seems to be too risky to have a big exhaust port sideways on , the ring will bulge outward in that direction, and even with the ring pin opposite I can see
    problems.
    All just to get rid of a header bend.
    The other thing that interests me about this project is that when I review the other engines in opposition ie up to 35cc on unleaded petrol , they all seem to be way ,way off the pace in both technology
    and Hp.
    its very easy , technically , for this engine to make 15 Hp @ 17,000 rpm - whereas it seems that many are super happy with around 8Hp.
    That is only 11.3Bar , 164 psi - bmep , very conservative in relation to many designs I have done.
    And at 17,000 + rpm as that is only 17 M/s Mean Piston Speed - again super conservative , with safe compression and completely normal ignition/combustion parameters.

    But as is the case in mini aero racing , the boaters seem all consummed with rpm , spinning them to 22,000 rpm even though the Hp peak is way back at 17,000.
    Is this something to do with prop efficiency - or some effect I am completely missing here.
    We needed rpm because the available props had limited pitch. We got around this by cutting and re pitching the blades, but that is still limited. We were thinking about a two speed, gear up transmission, but Covid postponed the project.

    I have a lot of data on the 35 cc engine we modified for straight line records a few years ago. The picture shows the stock engine with the stock pipe. Just shortening the pipe and header was good for a big power gain. We threw this away with a shorter pipe for more rpm. Water injection got back a lot of the low end which helped accelerate up to the speed trap. Below is the full article.

    Lohring Miller

    Click image for larger version. 

Name:	CMB 35 Hop up.pdf 
Views:	99 
Size:	1.16 MB 
ID:	347795
    Click image for larger version. 

Name:	CMB 35 with pipe.jpg 
Views:	130 
Size:	44.2 KB 
ID:	347796Click image for larger version. 

Name:	CMB vs Miller short pipe.jpg 
Views:	137 
Size:	66.3 KB 
ID:	347797

  10. #34675
    Join Date
    7th May 2016 - 04:34
    Bike
    1980 Peugeot 103
    Location
    Colorado Springs, CO, USA
    Posts
    26
    Quote Originally Posted by husaberg View Post
    The Rd125 an the Rd200 twins have smaller reeds but the same bolt pattern. as the RD250/350/400 and many others
    Not sure if the reed cavity area is big enough for Rd250 reeds without some welding, but MX100 DT100 AG100or similar might be about, in between size. Plus are the same bolt pattern.
    if I wanted to tune a small twin maybe start with a 200. As it s bigger.
    Taking measurements off of my computer screen on eBay ads, it looks like older DT100/RX50/etc reeds should work without modification to the cylinder and provide a good upgrade - they should fill the reed cavity nicely without having to cut, and it seems like they have about 30% more flow area. I suppose I could cut out the bridge on each side to gain some extra flow area as well, and cut new carbon reeds.

    Sim results on a slightly modified engine (wider exhaust port top width to 70% of bore, 190deg duration, 2-stage auto-generated "modern" pipe with 1.8 horn, 0.7 tailpipe, 3.5 center - just a first pass) aren't showing much improvement from bigger reeds alone. The bigger reeds with stiffer petals, however (0.15mm steel vs 0.25mm carbon, to get 1st resonance up to the middle of Dat2T's recommendation), gave 5-10% more power across the whole range, cool.

  11. #34676
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street Triple R/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    18,124
    Quote Originally Posted by mantonakakis View Post
    Yeah, main issue I will face with bigger reeds is width limitation. I think the opening in the 125 cylinders is about 34mm, approximately 3mm wall thickness? Not too much room to add bigger reeds. Stock reeds are good for ~20hp according to EngMod (21mm effective diameter should be good for much more than 20hp, though? Or maybe Dat2T is converting the two reed blocks into a single effective diameter? In which case, 21mm = 20hp sounds about right).

    Just did a short highway test - If I trust the speedo, about 55mph top speed with a very strong crosswind and a big loose jacket, somewhat disappointing. Seems to run out of steam by 9k, power drops off sharply after ~8500. Runs slightly faster in 4th gear than 5th. No EGT sensor, but cylinder head temp seems in the ballpark ~320F after a minute of idling following a long climb (more than 1mile at 8-12% gradient with 50% throttle or more in 3rd gear), jetting seems in the ballpark too. My cylinders are a little out of the roundness spec, but even so I was hoping for a little better with new rings and a fresh bottom end with the stock setup. I am at 6000ft above sea level, I'll run the sim at that altitude and see if it changes the torque peak. Biggest thing I notice is that the bike does not seem to rev out as high as the stock dyno would suggest... Power band start to hit, then it drops out too soon.

    EDIT: Sim results at 6000ft vs stock dyno:
    Click image for larger version. 

Name:	altitude_Stock.PNG 
Views:	103 
Size:	41.6 KB 
ID:	347784
    Perhaps some duct tape would help?

    Either that or a smaller jacket.
    I've been told. Dreaming`s free.
    Think I'll go, back to sleep.
    Everybody listen, voices in my head
    Everybody listen, do yours say, what mine says?

  12. #34677
    Join Date
    2nd July 2011 - 08:25
    Bike
    2006, KTM, 250 SX
    Location
    Sweden
    Posts
    272
    Quote Originally Posted by wobbly View Post
    Thanks everyone on the input . Seems to be too risky to have a big exhaust port sideways on , the ring will bulge outward in that direction, and even with the ring pin opposite I can see
    problems.
    All just to get rid of a header bend.
    The other thing that interests me about this project is that when I review the other engines in opposition ie up to 35cc on unleaded petrol , they all seem to be way ,way off the pace in both technology
    and Hp.
    its very easy , technically , for this engine to make 15 Hp @ 17,000 rpm - whereas it seems that many are super happy with around 8Hp.
    That is only 11.3Bar , 164 psi - bmep , very conservative in relation to many designs I have done.
    And at 17,000 + rpm as that is only 17 M/s Mean Piston Speed - again super conservative , with safe compression and completely normal ignition/combustion parameters.

    But as is the case in mini aero racing , the boaters seem all consummed with rpm , spinning them to 22,000 rpm even though the Hp peak is way back at 17,000.
    Is this something to do with prop efficiency - or some effect I am completely missing here.
    Nah, quite the opposite on the aero side, we want large diameter props for efficiency, but have to keep the tips away from M1.
    Id say the lack of ignition system is why we have to shoot for rpm instead of crazy bmep, glow plug ignition is a mess.
    We do run rear exhausts though, with ports up to 180deg width. Then again, we don't have to worry about a piston ring.

    Quote Originally Posted by lohring View Post
    For some reason, our testing showed slightly lower power on rear exhaust engines over conventional side exhaust engines. We couldn't come up with a good reason and set records with both side and rear exhaust Quickdraw engines. If the engine has open transfers like the early RCMK engines, you will get very rapid piston wear.
    Did all of the rear exhaust engines have those open transfers? If yes, wouldn't that excessive piston wear be a prime suspect for the missing power.
    That issue wont be there on the new design, that just leaves any potential issues with the ring... depending on lohrings answer that is.
    EDIT: Now that would be too obvious, surely lohring would have seen that connection if my interpretation were true...

  13. #34678
    Join Date
    7th May 2016 - 04:34
    Bike
    1980 Peugeot 103
    Location
    Colorado Springs, CO, USA
    Posts
    26
    Quote Originally Posted by F5 Dave View Post
    Perhaps some duct tape would help?

    Either that or a smaller jacket.
    I need a full streamliner!

  14. #34679
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    10,617
    Quote Originally Posted by mantonakakis View Post
    Taking measurements off of my computer screen on eBay ads, it looks like older DT100/RX50/etc reeds should work without modification to the cylinder and provide a good upgrade - they should fill the reed cavity nicely without having to cut, and it seems like they have about 30% more flow area. I suppose I could cut out the bridge on each side to gain some extra flow area as well, and cut new carbon reeds.

    Sim results on a slightly modified engine (wider exhaust port top width to 70% of bore, 190deg duration, 2-stage auto-generated "modern" pipe with 1.8 horn, 0.7 tailpipe, 3.5 center - just a first pass) aren't showing much improvement from bigger reeds alone. The bigger reeds with stiffer petals, however (0.15mm steel vs 0.25mm carbon, to get 1st resonance up to the middle of Dat2T's recommendation), gave 5-10% more power across the whole range, cool.
    we had a Ag100 which was the in between size I assumed the MX100/DT100 was the same looking at this it might not have been.
    maybe earlier was smaller same as the AG100? while later one are bigger.
    looking at the parts fiche the AG100 is likely the same size. as what you have.

    edit looked the RD125 looks smaller
    what I have found is one of the earlier CT2 which had the similar bolt on manifold which would give a straightish inlet
    which looks te same size as the AG100 its made for a 22mm carb and I bet the stub is available cheap.
    https://www.allensperformance.co.uk/...ormation-page/
    okay found this also
    https://yamaha-rd125.blogspot.com/20...a-rd125-a.html

    https://www.cmsnl.com/yamaha-ag100h-.../#.X76jzGgzaUk


    https://www.ebay.com/itm/Yamaha-RX12...e-345-13613-70.
    Yamaha RX125 DT100 DT175 RT180 RD250 RD350 TY250 MX100 Reed Valve 345-13613-70
    the reed dimension or the RD250/400 are well known and the late YZ85 is a single petal design from the factory and V force are available.


    http://erlenbachracing.co/reedcages%20mods.htm
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  15. #34680
    Join Date
    28th August 2015 - 00:01
    Bike
    1975 Hodaka Wombat
    Location
    Eugene, Oregon, USA
    Posts
    230
    The side and rear exhaust engines we tested had either liners or standard closed transfers. Quickdraw once made crankcases for both types that differed only in the bolt pattern and cutout areas for the transfers. I have one of each type that are going into the proposed opposed piston engine. The ringless piston engines used in smaller models don't seem to have the same issues, but I'm not aware of anyone who has done careful test comparisons. Boaters use a variety if bent headers to run all types of exhausts. Below is the most extreme, a 180 degree header. I've run one of these engines and it was definitely more powerful than the older rear exhaust version. However, the one piece design of the new version was stiffer along with a bigger intake and other factors.

    Lohring Miller

    Click image for larger version. 

Name:	7525-m.gif 
Views:	86 
Size:	19.8 KB 
ID:	347803 Click image for larger version. 

Name:	9181.gif 
Views:	95 
Size:	22.0 KB 
ID:	347804

Thread Information

Users Browsing this Thread

There are currently 14 users browsing this thread. (2 members and 12 guests)

  1. Ramamstf

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •