need some advice!!!

[jake1113]

74 yamaha tx500, runs great at idle and when first riding as it warms up the right cylinder seems to cut out and in turn creates a jerking motion while riding, it has points ignition, my buddy thinks it's in need of points and condensors seeing it's orignal but i think it's something else perhaps fuel related. the reason i think this is if it were ignition i would think hot or cold it would run like crap, but i think theres perhaps crap clogging the carb and when it starts out the crap is on the bottom and gets mixed up and cloggs the carbs, if you let the bike rest for a minute it starts right up and runs fine even warm for a few minutes and then does it again, any advice is appreciated or if anyone has had this problem please chime in :-\

 

[Big R]

Original coils? When coils are dying, they work great at lower rpm's and when they are cool. They miss at higher rpm's and will die when they get hot. Once they cool down again (about 20 minutes) they run again.

 

[jake1113]

yeah they are orignal so yeah i thought about that as well, but just to clarify more i was having this problem and pulled into a parking lot for about 2 minutes and when i pulled out on to the road it ran fine for about 2 blocks and then started doing it again, but i will defintley try some coil we still have another parts bike to pull some off my bike has orginally 9k or so miles the last parts bike i believe had around 22k. or would you just buy some new ones?

 

[Big R]

If you plan on keeping the bike for a while, buy new ones AFTER the current ones are proven to be bad. New coils ain't always cheap........

Could it be a vacuum problem with the gas tank or something?

 

[Jared]

My car had a similar issue, check for vacuum leaks.

 

[pterodactyl]

A dirty fuel filter?

 

[Big R]

Just read the first post a little more- Jake, have you pulled the float bowls off yet? That should give you a really good idea if your carbs are getting clogged or not.

I don't know anything about TX carbs, but there should be some type of vent on them as well. If the carbs or the tank can't replace gas with air, it stops flowing gas.