RD4ME

Project looks to be coming along nicely. I'm interested in hearing how you like that OKO carb when you get it all back together!

Thanks for sharing Jeff! Looks like we're having an early spring in Ontario - so timing is just about right to start thinking about getting my TY out of the shed! I'm glad I have this thread as it reminds me where I left off before winter hibernation!

Ok - many thanks. I guess I’ll start tracking down a seat cover for my 250. suggestions are welcome!

Looking for a new seat cover for my 1978 TY250. There seem to be more available for the TY175. I was wondering if anyone knew if they were interchangable? Thanks!

I've had the carb out again and there's no blockage in the jet or the passageways. But it does still require the Air screw to be in all the way to run right. Bmonk dropped a logic bomb which has me putting the brakes on my bigger jet order. I sprayed carb cleaner around the base gasket and intakes - nothing seems to get sucked in and the revs don't change. I've had the flywheel off and don't see any evidence of the seal leaking - although if air is being pulled in I don't knwo that I would. Haven't had the clutch side opened up yet - so I guess I could go there. Just wondering if I'd be doing any harm to it by riding with the Air screw all the way in? I guess if the issue got worse - there'd be no further adjustment - but at the same time it might conceivable work itself through. By the way - I had my first "off" yesterday when riding it in minus 11 degree weather. The grass was frozen and slick and I clutched-in and put the front brake on; due to my sticking clutch plates the back wheel kept turning so I pulled the brake harder - locked it and went over. I rolled off with nothing hurt by my dignity! I quickly got up before my wife noticed...she would have been concerned over the big skid mark I made on the grass!

OK - great - I'm going to order a #37.5 and a #40 jet. I've removed my stock #35 from my Mikuni VM26SS and have measured it. Pretty certain it's the M28/1001 series - but hoping someone might be able to confirm?

Thanks Feetupfun for the great explanation - I think I can follow those instructions. But the good news is - I may not need to! The Snap is Back!! It looks like I've made a break through. I pulled the carb off to install my new needle and seat - and pulled all of the jets and doo-dads out again and gave it full clean/blow out. Then when I was adjusting the Air screw - I noticed as I screwed it in further - it revved-up faster. So I screwed it all the way in and took it for a spin up the street - and it felt like a different bike. The front end came-up high with just a blip of the throttle without any pulling on the bars - it was amazing! But then when I screwed out the Air screw to the 1.5- 2.0 turns - it lost its snap again. So I'm not sure if when screwed-in all the way it gets more or less air - and why it needs it. But I guess that's what I need to figure out next - but pretty pleased that I've found the power again!

Thanks. I did try the Q-tip in the drill trick using some metal polish - but couldn't get it to stop leaking so I ordered a new needle and seat kit. I also spent the last weekend de-coking the exhaust. I filled the pipe with casutic soda and let it sit overnight. I wasn't that impressed with the result - particulalry since that chemical is so dangerous. So I used a blow torch to burn out the carbon and fed a steel cable through throught he pipe and hooked it up to a drill. That worked much better and removed a bunch of carbon deposits - pipe was quite clean afterwards. I really thought that would solve my power problem - it might of helped a touch but I'm convinced this bike isn't putting out anywhere close to what it should be for low-end power. So that's my list completed - the only thing I haven't done is the timing. I pulled the flywheel and the points looked new - and I have good spark. I haven't found a dumbed-down step-by step guide and I don't have a way to accurately measure the piston position for the advancing of the spark - and I'm concerned I'll do more damage than good! But any advice on where to go next is appreciated! 1) Spark Plug - done 2) New Gas/Oil mix - done 3) New Tranny oil - done used Rotella 15W40 4) Compression test to veriify my foot feel - done 5) Air box check - Done 6) Carb clean - done 7) Clutch adjustment - done 8 Exhaust check/de-coke - done

Thanks thai-ty. I don't fully blame the bike for the lousy wheelies - but I should be able to flip one of these over backwards - and I can't! Scifi also suggested to try a lower gear. If it ever stops raining I will try it this weekend!

Hi Guy53, I've got to do something with my cluthc - the pull is way to stiff. Can you let me know where I can buy the extended clutch arm (TY250) - I'm in Ontario. Thanks

Interesting - thanks. I'll give that a try before the snow hits the ground!!

We've had a fair amount of rain this week and the knobbies have being doing a number on the grass. Hoping the leaves fall soon so my wife doesn't notice the chunks missing from the lawn!

Too cold to do much today so painted the muffler. Zipped around yard with it out a couple of times. More noise - no extra power.

Thanks Scifi, Section and Tony - this has been so helpful! I swapped the o-ring on the main nozzle tonight - still leaks so that's off the list (and it did fit because I can feel the resistance when I put the bowl on). You can see the scoring on the needle - I'm really hoping that's the cause of my leak. I found a place in the US (jetsrus) that stocks parts for the Mikuni VM26SS - so might get lucky going that route. I'm fortunate that my bike came with a well used owners manual - it's quite detailed and ha been very helpful.

Thanks for the links and additional tips. I inspected the needle and seat and there's no obvious signs of wear - but given that the float does float - it's all I can think of. I believe my bike has the stock mikuni VM26SS which are not easy to get rebuild kits for. I did find a needle and seat at Yambits in the UK - so I have an option there. I will try replacing the the o-ring first - is it #4 below - the one that fits on the main nozzle? Thanks!