guy53

Thank's for the pointer David, I checked my notes this morning and I'm running at 3.3mm so not that far. I will pay a visit to a friend of mine about the combustion chamber when I get a chance. B40rt, I haven't seen a Dellorto on a TY here, I've always heard they worked well but where more difficult to tune. Buy

I had check their site before posting and if I go the OKO way, they'll be the one I contact. Guy

Section Swept, I have 2 Yamaha Mikuni that I fitted on the bike, the one that originally was on is the one that use to make the test. Quite a few times after testing a new setup I change the carb for the '' other '' original to compare. Also I've been telling fellow worker to make change one step at a time and keep notes of the change and the result on different machines for more than 40 years, so I practice what I teach. I know many will change low speed jet not be satisfied play with the needle, no go change float setup....and than .. what was the original setup. I think the Wes exhaust to be an improvement. I did not mentioned that I ride more than I do sections so the motor don't get hot than cooler than hot again. David, your theory on the combustion chamber is interesting, if you have link on the info on that I would be grateful if you would pass it on. I have a couple head on the shelf, I would use one for test. I am shocked at the timing you set your bike, mine is setup at around 3mm BTDC. We had a couple of days with the temperature on the plus side, I think the left cover is going to be off the motor soon. Guy

I have a B model 250 with the original Mikuni that I've been trying to setup for a few years. The motor as a .005 inch head gasket, is on 3rd os, the exhaust port is '' lifted'' .020 inch, the rest of the ports are not modified, not really polish but clean. There is no modified reed valve. I run Shell super gaz with a good oil at 50:1. I fitted a Uni Filter and the motor is equipped with a Wes exhaust. I played with the timing without any real improvement.I have been fiddling with the needle eight, low speed and main jet, air screw etc. but the motor is always running hot at close throttle to 1/4 open . I fitted a VM 26mm played with it all of one summer and went back to the original Mikuni. I am thinking maybe an OKO carb might cure the problem, any experience ? Guy

You should also have a look at your cable and it's routing, I know they are different, but the clutch on my TY 250 is smooth and predictable. I change the cable and keep it well lubricated, I also use a longer lever. It is very light to a point that some of my friend thought I ad taken spring out.

A closed mind is worst than no mind at all Guy

I know I should not say that but the clutch is such a good friend in some situation. Guy

I don't think numbers are important here as electric motor do not delivers power the same way a combustion motor does, and by the way, the first mono where laughed at. Guy

Have you tried to loosen the fuel cap when it dies ? Guy

There might be 10,000 km of off road trails in the FQMHR but I ride either a Ty 250 or a Beta Rev with no light or turn signal, and frankly I'm not interested in riding full throttle in a field. As for the ATAQ, they are a great bunch of guys that organise competitions, and there is also a vintage trial group that also organise comp that I attend and really enjoy. But I like to ride ( trial terrain ) not compete. I like to ride just for fun. As for you Leosantanalg, don't throw the line too far, you might see me coming around one Saturday morning. I went to Vermont last year to meet the guys, the Vermont Plonker, and I can promise you that if I still have my bike I will be back this year. Guy

I'm in Quebec and I thinking about selling my 2 bikes because of land issue, I can't find place to ride. Guy

At least I'm not alone ! Guy

Dunlop GP Lots of traction, good price Guy

I use Lysol between stripping and washing, I don't like it when I can call my helmet and it crawl to me by itself. Guy

Try the cold water treatment. Guy

I had time to do a little work on the motor yesterday, as you mentioned David, the crankshaft on the clutch side is different. From what I have measured, they would be interchangeable if you use the primary drive gear of the same year as the crank if you do not use the oil pump. Also the axle main 14t ( 434-17411-00 A model ) and the clutch ass'y won't be interchangeable. I don't have anything to check the weight of the crankshaft , but the A model look heavier, that maybe one of the reasons Yamaha added weight on the flywheel ( they sure overdone it ). On that subject, I always take the ring on the flywheel and use an A model flywheel on my B. Guy

I'll split one of the A base that I have, I thing it's worth it now. Guy

I split the base and I think I had reasons to fear. I only have A model parts list but I'm sure everybody will understand. On the output shaft ( on witch the chain sprocket goes ) called in the manual part 17 axle drive, the last gear, part 18, gear 2nd wheel is not free as I was expecting it, So is that shaft on a D model interchangeable with one from an A model ? I could use the complete shaft ( with all the gears ) Guy

No luck here, I have 2 friends who ride KT, but none of them have tried that ( at least they won't tell ) Guy

So all transmission, clutch and crankshaft are interchangeable. Guy

Any parts from A TY A model I could use T completely rebuild a D model ? Guy

Jon, winter is coming ! Guy

I wonder if anybody as ever put a 250 TS TY and a Mono TY motor on a scale ? I am in the process off rebuilding a TS and find the motor heavy. Guy

Space the shock with washer.

I would not be ashamed to ride one ! Guy