fishhead Posted April 17, 2013 Report Share Posted April 17, 2013 I have a TY250 (Yamaha Trials) -1974 that is in great shape. It starts up fine, revs, as well as idles just fine. When I place in gear and accelerate it bogs down. It's like it's choking for fuel. I can hold the choke down and this helps a bit, but eventually dies. Does anyone have any idea what might be causing this. I've been through the fuel system about three times already. Taking all advice as would like to get this thing up into the hills and start riding the ridges... thanks for any help you can provide.. Quote Link to comment Share on other sites More sharing options...
copemech Posted April 17, 2013 Report Share Posted April 17, 2013 You state you have gone through, but did you remove the jets and pass a fine wire thoough them? Many have been fooled! Insure the tank is venting and flow to the carby is good as well, just thoughts! Quote Link to comment Share on other sites More sharing options...
b40rt Posted April 17, 2013 Report Share Posted April 17, 2013 If it restarts fairly quickly it would point to fuel, if not, ignition. 1 Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted April 17, 2013 Report Share Posted April 17, 2013 OK assuming all jets vents etc are clear and that the jetting slide etc is correct is it on "electronic" ignition or points? if points swap the condenser as it's surprising how often these let you down and don't just assume that if it's a new one it's ok. Quote Link to comment Share on other sites More sharing options...
tony283 Posted April 17, 2013 Report Share Posted April 17, 2013 You don't give us many clues. Have you recently acquired this bike? What altitude are you riding at ? What carb is fitted and what are the jet sizes, cut away on slide, needle setting ? What plug are you using and what is the gap? Has the ignition system been changed ? What state is the air filter and exhaust system? Is the reed system good? Are you using pre mix and what ratio ? Fill in the blanks and I'm sure we can all help. Tony 1 Quote Link to comment Share on other sites More sharing options...
charlie24 Posted April 21, 2013 Report Share Posted April 21, 2013 Crankcase seals cause this. Easy to do. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.