Flyingdog's cylinder

[racerclam]

Tis is Dougs o3 cylinder I just compleated porting for his loooong haul Ride from Utah to Athena this year to make the ride more pleasurable and torquey

Rich

[bchappy]

Nice work again. Looks like it will do the job. Be interested to hear how it runs.

[Kels]

Does anybody else think that these cylinder alterations are not conducive to a low end power increase?

[bchappy]

The key is to not alter the timing that the exhaust port and the transfer ports open. Widening the ports only lets more fuel mixture in.

[Charlie R]

I predict 12 pages......

[Zyx]

I would predict this would be roughly low end neutral and probably more or less high end neutral, although with additional fuel mix available at lower speeds with a bit less reversion, there could even be a little gain on the top. I think the aim here is mid range boost. Rich could speak to whether timing was altered, but I think not.

[racerclam]

I just spent 15 minutes typing a response then my stupid computer delesated it when I hit submit now I don feel like redoing it , maybe tomorrow .

Rich

[taber hodaka]

Rich I guess I am not the only one that happens to. "computers". I think with a reed you are going to have more power low and high especially if you tune it and stay with good oil.-----------Clarence

[DGardner]

I can give a true before and after. Before....I had RK Tek do some port work with one of there heads, PWK 28MM carb, circle F pipe, thunder produces torque wing, MZ ignition, 16/47 gearing. The bike had a 75mph GPS verified top speed and there is a hill by my house that I could pull about 60-65 MPH. It ran very hard from bottom to top. After.....I shift to top gear at 55 MPH and it slows down...it can't pull 5th gear and the hill can now be pulled at 45 MPH. This is the motor that I was going to try and ride 1000 miles in 24 hours so I can't run high compression or have the ignition advanced to far or it will just kill it. DG

[racerclam]

Ok Im trying again. First nobody says this cylinder is for trials use ! Ist for crusing down the Highway . Tthe transfer volume seen here does NOT! take away bottom end but will help with torque regardless of where the port timing is put . the transfers here are only equalized to the factories highest highest one as is the boost port this only improves response. The width of the boost port exits enhanses scavenging at the rear of cylinder , sthe mor actice area at the rear the better. The intake port volume is increased enough to change the boost port angle to 45degrees this again is a torque booster. And if intake port volume is an issue then we can assume that modern case reed engines dont run . I also added a case port to connect the intake port directly to the crankcase . The better access to crankcase signal with out piston interference the better . On a reed engine the back of the piston is only need to hold the piston where it belongs which is why they are swiss cheese.The exaust port here is the same height as a stock combat wombat BUT! only For 1/3 of the top to iniate a pipe signal and allow a better cruzing rpm and tapers down to a trapazoid shape there again improving power at all speeds . This is NOT! an experimental cylinder I have many running out there with grear results and can be dialed to intended use by pipe selection. I have this on one of my bikes ( my trail bike ) with a combat wombat pipe and a 36mm carb and has lots down on the bottom and pulls great every where. Scott hatch runs on too with greart results . Brian Briggs runs one with astock super combat pipe and runs great. Bchappy has one to with a HT3 pipe. Billy Burns also is running one with a HT3 pipe and has power every where . I don know why Dougs bike is not working right , There are other factors at play , un fortunatly I cant tune it from here . Also Harry Taylor taught me these concepts and they work . Ok now fire away !

Rich

[Kels]

Ok Im trying again. First nobody says this cylinder is for trials use ! Ist for crusing down the Highway .

Tthe transfer volume seen here does NOT! take away bottom end but will help with torque regardless of where the port timing is put .

Aah... With all due respect.. This is simply not true! To get a column of F/A mix to move you require pressure. Inertia is ALWAYS a Player!! and the pressure ratio is critical.

the transfers here are only equalized to the factories highest highest one as is the boost port this only improves response.

The width of the boost port exits enhanses scavenging at the rear of cylinder , sthe mor actice area at the rear the better.

Again, with all due respect... Not correct
The intake port volume is increased enough to change the boost port angle to 45degrees this again is a torque booster.

And if intake port volume is an issue then we can assume that modern case reed engines dont run .

Intake volume plays a huge role in the carb signal and the case volume plays a huge role in the pipe effects.. This is a critical area and will directly effect the power-band of the engine. Stating that this volume is not a player and that you can have as large a volume as you want without effecting the power-band is simply ridiculous

I also added a case port to connect the intake port directly to the crankcase . The better access to crankcase signal with out piston interference the better . On a reed engine the back of the piston is only need to hold the piston where it belongs which is why they are swiss cheese.The exaust port here is the same height as a stock combat wombat BUT! only For 1/3 of the top to iniate a pipe signal and allow a better cruzing rpm and tapers down to a trapazoid shape there again improving power at all speeds .

EVERY exhaust port opening initiates the exhaust process.. The shape is a player as well.. Your shape is not bad... But to make people think that it is doing something "special" is misleading. The port is substantially higher as well over stock height.

This is NOT! an experimental cylinder I have many running out there with grear results and can be dialed to intended use by pipe selection. I have this on one of my bikes ( my trail bike ) with a combat wombat pipe and a 36mm carb and has lots down on the bottom and pulls great every where. Scott hatch runs on too with greart results . Brian Briggs runs one with astock super combat pipe and runs great. Bchappy has one to with a HT3 pipe. Billy Burns also is running one with a HT3 pipe and has power every where . I don know why Dougs bike is not working right ,

There are other factors at play , un fortunatly I cant tune it from here .
What other factors are in play?? NOTHING was changed but the cylinder and case work you did and the bike lost major power. Again, the cylinder and case mods were the only altered from a previously great running engine.
Also Harry Taylor taught me these concepts and they work . Ok now fire away !

Rich

[racerclam]

I do know that it takes pressure to get air moving be it atmospheric or pumped as in a 2 stroke . And if these transferes do work Imut be imagining all the ones out there that are working . The Hodaka transfers are very small in stock form compared to other makes that either larger or more transfers .. This intake port volume yes plays a part , but this is a proven method on the Hodaka of laying back the boost port as well as dropping the floor, its not widened or raised, again Many are working great . The exaust port always begins the pipe signal but the amount of the initial opening determines much, Hmm! again works good on everyones but Dougs. I know theory very well and also what works , this isnt my first time around the block. o why is every ones working and this one not ? There is something being a foul . Without spending the rest of the day comparing theory notes , if all works but this one whats up ?

Rich

[Zyx]

On those machines for which this porting worked, are there other attendant specs that would alter the result? Carb size, carb modifications, air filter, exhaust system, deck height, piston choice, gearing? Aftermarket exhaust designed around a stock engine paradigm may not work well, or at all, with a modified engine. Without details, it is hard to draw usable conclusions. Of the several examples mentioned, and assuming they all used the same base cylinder and were ported the same, still the only thing each has in common so far is the porting.

Also, the owner said a couple things that might have an impact. Can't run advanced timing or high compression. Oh? Is it a given that these things would "kill" the engine, or perhaps timing was deliberately set back, and a low compression head or thicker gasket was used that could account for some of the observations.

Also, when the new build runs out of oomph is it due to rich condition, lean condition, or lack of vacuum? Do we know? If not a jetting issue, then perhaps spark is simply too far retarded to do the build any good.

Arguing and understanding IC theory is a beautiful thing, and intelligent people can and do disagree, but it is too soon to conclude that the porting here simply won't work. Clearly it has done in the past, so it may yet do here. I would look for ways to identify direct cause for each symptom, and work on changes that could rectify them. One may start by assuming that it is the porting that is wrong and that this build will never work, but doing so won't get anywhere because the only way out of such thinking is replacing the cylinder, which may or may not be a handy option.

Unfortunately there are not enough good cylinders laying around to use a spare as the experimental unit, and there may or may not be another 03 available just now. For the moment I would at least try to get out of this one what may be lurking there. Check the timing, and if it is correct, try advancing it slightly. If a timing light is handy, try verifying that the running timing is right, and check for total advance at mid to high range rpm, rather than relying on static timing and hoping that the ignition system is doing its job. Try a hotter plug. Check compression. Check for air leaks, since the engine was by definition just apart. In other words, try some diagnostics. There is more likelihood of that getting somewhere than arguing over theoretical perspective.

[racerclam]

Yes Gregg all machines are running different pipe carb combos as well as ignition, carb calibration is a who knows ? Personally I prefere to adjust the timing to what works and a static setting is someplace to start . You give it what it can take with out negative affects , THEN re check and record where it ended up. And checking with a light is the best method then as you said the advance curve can be checked other wise you just cant know .

Rich

[Kels]

Yes, with any 2 stroke.. every change made will effect every other area..

But with this particular build ALL that was changed was the cylinder and case work..

Flyingdg adjusted timing and jetting to TRY and get this new "TORQUE" engine to produce the "torque" .The only thing these mods did was LOSE torque and HP..

Engine is tight, no leaks, everything is in its place . Doug is NOT new to rebuilding 2 stroke engines.

What shorty is stating would be 100% true IF the engine and all its "other" components were not working good BEFORE this porting and case change..BUT, in this case, these other components were proven to be good changes..

This engine is so far off its mark it is un-rideable... No jetting or timing change will restore power losses in this magnitude.

This WAS a REALLY good running engine Also the reeds got changed.

It is ,clearly, obvious what caused the engine to lose performance.

[Zyx]

Okay Kels, now you know something about the situation that no one else seems to know, that is, that timing and jetting were changed to try to get this build to work, and yet in the same post you say that the ONLY thing changed was the porting. So which is it?

I would also have to disagree with the premise that because the blend of modifications were working with the porting as it stood before, the same blend of mods must necessarily work now. Why would you think so? Start with an engine that is working well. Doesn't matter which one. Now put on a carb that is twice as large. Will everything else now work perfectly? No. Is the carb too big (and my example to simple,)
sure. But the generality holds no more true in my example than in yours that you can change some major component and everything else that worked before will work now.

You also said that there are no leaks etc., and you may be right, but sounds to me like you have info not shared here. Better if Doug shares this info since he is e man on the scene.

What was said by Doug was that he can't run advanced timing. Advanced timing is a term of art. Advanced versus what? So the question is what is the timing set to now? That it may not have been changed means nothing if it isn't right to start with, and one build may be more tolerant of late timing than another. An Ace 90 is not very picky, and you can set timing with a feeler gauge and it runs fine. A Super Combat is far more picky about timing. Porting is quite different between the two, and that is part of the difference here. Point is that it is an ASSUMPTION that if the timing worked before it will work now. Same with carburation. Same with jetting. These are just testable assumptions. May be time for some testing.

I am sure it is disappointing to get a custom port job and have it not work out of the box, but was it offered as such, that it would work without alterations to critical components? I don't know. In my opinion the porting here is a radical departure from stock or even from mildly modified. Perhaps some work is still needed to optimize the changes that were made.

First place I would start is timing. If the timing is set with less advance than recommended, put it where it needs to be. Even if it is then too advanced, it will announce itself in short order by pinging. So, advance it to the edge of too much, and back off. But to deliberately set it retarded on the assumption that to do otherwise would kill it is, I think, misplaced. I am not saying to run it as advanced as it will suffer and still survive, but to run timing retarded, especially when building a high performance engine, is counter productive and may in fact produce all the symptoms currently observed, so yes, timing can in fact make a change of this magnitude. If you doubt me, go set your bike to TDC and let us know what the symptoms are.

As for the pipe, there is no reason to think that if it worked for a lower output application that it will work here, but frankly the described symptoms don't sound like the wrong pipe. Not yet anyway.

The torque wing is okay. Not optimal perhaps, but okay. Is it still in there?

And Doug isn't the only person who has been building engines for years, but that in itself is no guarantee. I have been at it off and on since the '60's but I still make mistakes about as regularly as I ever did. I also want to think that this problem is not the fault of Doug in his building technique. I only suggest using diagnostics to eliminate assumptions because it is the right thing to do no matter how good you are.

I once ported the heads on a 350 Chevy for the kid next door. That was the only changes made to his '69 Camaro at that time, but he had already put in a high lift cam. The change in head porting made it go from easy to start to impossible to start because he was now making full use of the cam. He was annoyed but welcome to the hot rod world. All he needed was a high torque starter. Ran like a raped ape. It wasn't that the head porting was wrong, but that it opened Pandora's box unexpectedly. Maybe this port job has done the same, and it is time to either can the project now, or embrace it and find out what now works and what doesn't.

[Kels]

Shorty.. I think assuming that this cylinder/case combo was just thrown on there, engine started, and ran would be an incorrect assumption on anybody's part.

Almost 2 full days were spent trying to get this engine to gain back the performance that was lost..

Doug was on the phone constantly with the builder and did what was asked to no avail.. (except install a 32mm carb ???) Nothing made this engine perform.

To the trained eye, it is VERY apparent, how these changes would effect the power characteristics of the engine.. Then the real world results only verified this.

As stated before, MANY things were tried and nothing made this engine perform.

ANY engine that is going to travel 1000+ miles WOT can not have a lot of compression or timing advance. It will simple not live.. This really is not up for debate.
The timing on this engine is NOT set less than ideal.

Please remember, this is and never was "race engine" it was a trail engine running on pump gas and to be held WOT for EXTENDED PERIODS..

There has been further developments recently and the engine is performing much better..

The combination of "add on" components that are on this bike do nothing but make the engine perform better. This engine has gone through MANY stages of development. There is more money in the engine than the bike is worth. It has been directly compared (via riding together) to an identical bike during ALL these different stages of development. There is NO COMPARISON how this engine runs (ran) with respect to a good running stock engine. The changes made have ALL been verified as to their validity and contribution... The work Doug has done has ALL been documented and scrutinized beyond belief.

This latest endeavor (see pics) is no exception!! The mods were installed, TUNED, and tested, retested, retested,, etc etc etc... The results are the results and can not be disputed. Unfortunate as it is... this is the reality. There no timing or jetting change holding it back nor is there a mechanical issue holding it back.. What is holding it back is cylinder and case work that does not belong on a 10-12HP engine.

[Zyx]

Well, see, you did have more information than was posted by Doug. Would have been helpful, don't you think, to share the details up front rather than parse out information as zingers?

The 125 made more than 10 hp stock. My old 100B made 9 with a 20mm carb. But all that aside, if Doug wanted an engine that would run WOT 24/7 why were changes made to begin with? If it wasn't broken, what was the fix for? I don't think any of our 40+ year old bikes are good for WOT down the highway, but even if you want to go that route, advanced timing is not in and of itself contraindicated. Correct timing for the intended use would be best, but there is no fixed answer for what correct timing is. Timing advance and increased compression make demands on fuel quality more than anything, as long as within reasonable bounds. Road racers live on the ragged edge, run WOT with advanced timing, and yet seem to live from day to day. So while I agree in broad terms that high compression and advanced timing are not NEEDED to run 65 on the highway, I do disagree that such settings will necessarily kill any engine. If you give it the fuel your build demands, you can get WAY WAY more than 18 hp from a 125 without building an all out racing engine.

I for one have not been trying to shift blame, not one way or the other. Instead, I am trying to explore possibilities that apparently you and/or Doug were quietly exploring yourselves. You may yet find what is going on here. Some several other folks have successfully used these same porting specs. It might be worth the effort to contact these folks and find out if they had issues and what they did to overcome them, because it appears there are several similar to nearly identical builds out there that are working. Unless VooDoo is involved, if it works for a guy on the east coast, it should work for guys further west. Ask to be put in touch with these other folks and see if they can help.

Or, you can just give up on the idea, and vent your frustrations here in what would otherwise be a neutral venue. Choice is yours. If Doug wants help from the peanut gallery, he can ask, but the details should come through him.

[DGardner]

Rich....knew what pipe, carb, ignition and head I was running.....He called me and said "I can make you a torque monster" then after it wont run tells me that I need a 36mm carb, change the head to raise compression and change the pipe. This was not to be a race motor and he knew that. If other people would like to use him please do but for me never again. DG

[bchappy]

I don't think it has been stated but what cylinder was on the bike that was producing all this speed and horsepower. I remember you said it had some porting done by RK Tec. Just wondered how wild the port timing was on it. I will mentioned that the case and cylinder porting Rich did for me made mine a couple sizes rich on the main and needle so I had to drop a couple sizes to get it to run right. It is an MX machine and I have never tested it for speed on the highway but it sure gets from one corner to another spinning all the way. You guys can kick the porting all you want but for my money it was worth it. Kels, it seems you have some affiliation with RK Tec as you show their website under your login info.

[DGardner]

The cylinder is a 03 porting was a very mild port job that just worked good. Again Rich knew I was not making a race motor...your mx motor may be the best ever made and I'm glad it worked out for you.

[Kels]

I don't think it has been stated but what cylinder was on the bike that was producing all this speed and horsepower. I remember you said it had some porting done by RK Tec. Just wondered how wild the port timing was on it. I will mentioned that the case and cylinder porting Rich did for me made mine a couple sizes rich on the main and needle so I had to drop a couple sizes to get it to run right. It is an MX machine and I have never tested it for speed on the highway but it sure gets from one corner to another spinning all the way. You guys can kick the porting all you want but for my money it was worth it. Kels, it seems you have some affiliation with RK Tec as you show their website under your login info.

I am glad your engine works great..

Have you tried taking away the high compression and advanced timing and see if it still works well? Do you run WOT for 100 miles straight on 91 octane fuel? What octane fuel do you run in your MX machine? What is your compression ratio?

Those that understand porting, know that this type of porting will not produce low end gains..The build was for low end gains.. The reality was that the low end SUFFERED greatly with these mods.. This is undeniable.

In fact, removing the semi case induction IMPROVED low end and top end power..

Here is the real issue..Besides the fact that the engine changes produced much less power than before. The builder has NOT offered 1 bit of compensation for this... Doug is out a very rare cylinder (fortunately he does have another one that is unmolested) and his cases are also beyond returning to original form (again, Doug has another set of cases as well).

I think all of this would have been a "non issue" if the builder would stand behind his work and offer Doug a new cylinder and cases . Then he can get these modified parts back to pass on to the next person. But this has not happened .

IMO--> when a product does not perform as advertised, then the shop should do their best to make it work as advertised. Asking the customer to spend another large sum of money to make the product work is not an acceptable form of "help" IMO.. The builder knew the application and the current mods done to the engine. The cylinder and case work should have been designed around these known parameters and they were not.

[Charlie R]

Sorry to jump in here but Doug...I sent a PM. I do not have your shipping address (or can't find it I should say). It appears that you have located an 03 cylinder. Do I still need to send one?

[racerclam]

OK doug , I didnt say you needed a 36mm carb but that I was using one and larger would be a plus, also that Mine uses a combat wombat pipe and head , and it works great with lots of bottom and mid . Said I had no experience with thew circle f pipe. I suggeated you just throw the pipe on there to try and try a head .
Kells , putting theory asside , Does it really make sense for me to do all this work and send it out ( without wanting any money until Doug could afford to pay ) ? Pretty stupid on my part if this was not a proven method, dont you think. I am not here to experiment on people and just suck out thier wallet..
Everyone else here please note ! I have an un tarnished reputation and always go the extraa mile to please my customers, I am honest and fair.

Doug, It not right that you blast me here and go to an outside source without working with me to help you. If I have an issure with a product I and most people will go to the source to figure it out. Thats thats right thing to do. I just wanted to help you so I did all in good faith not requiring anythin from you , I didnt even ask for money to cover shipping or for the reeds , thats out of my pocket . Who else would do that . ? This morning i called you and asked you to call ne and update me with what you have done , and you didnt ! Not right! WEll I want to please you and I will send you a new enduro cross cylinder if you send me yours, I dont have cases though. Thats all I can do since you wont work with me . This isnt the place to work out this stuff but I guess its the way you prefere to. Let me know . Preferably by phone call.

Rich

[taber hodaka]

Conflict has no winners. There is hostility and anger here. These things left unchecked can turn into hatred. The Hodaka Forum is not the place to dress somebody down. We are all here to help each other enjoy our hobby sport or just remember the best part of our life. I see nothing here worthy of a wasted friendship. To me there is only three ways to resolve conflict, In person, phone or letter. A public website is not the place. We all should memorize the poem IF by Rudard kepling Cant spell. ------------Clarence