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fuel supply issues

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by idontlikemondays, Aug 25, 2007.

  1. regarding a VTR250 2002, 52000kms

    after doing a valves clearence check last weekend, the bike has given me all sorts of grief since. i know the carbies are slightly out of balance, and i am waiting on a vacuum gauge set atm. but the choke isnt working. ie when i cold start, i put on about 1/4 choke, she'll idle ok for about 10 seconds, then start to miss.
    it is running rich too.
    at operating temp, at steady RPM, she'll sometime miss when cruising, accelartion is fine, but not as strong as it should be. would carby balance affect choke? i wouldnt have thought so but just checking. im thinking choke is stuck on, could cable routing cause this? at steady RPM cruising, apply choke and bike will miss untill 1/2 to full throttle, then accelerate fine.
    on start up yesterday, a MASSIVE amount of smoke smelling like petrol came out the back.
    its the first time she's played up like this, and not the first time ive had the carbies off or done a valve clearence. she is just genrally running like shit.

    vacuum leaks in the manifold did occur to me for rough running, but i didnt think this would be the case if its running so rich.
    sticking carb slides also occured to me as one was not as quick to return to closed when i was checking the carbs when they were out of the bike

    im really just after some thought and suggestions till i open her up again tomorrow arvo.

    any ideas would be greatly appreciated, as i dont want to ride her anymore untill i get it fixed, if its running so rich.


  2. I thought it was the storm, you know running rich, smoke and smelling fuelly and all.

    I would be looking at the choke cable routing, it could easily be the cause of partially stuck choke, and the smoke and fuelly smell on startup. The strange thing is the missing at steady cruising rpm when you apply the choke, but after about 1/2 throttle it stops missing, in theory, if the choke was stuck, then when you open her up with choke ON, more fuel will see it keep missing, and plumes of black smoke.

    It could be a float is stuck, and flooding a carb, or even a CDI problem that is intermittent. How reliable is the miss when you apply the choke? Could also be the choke is adjusted poorly at the carb.

    Hard to say without seeing it.
  3. thanks for the reply tweet. a stuck float didnt occur to me, but yeah, i've had a couple of problems with stuck floats in the past. might be time to rip the carbies apart :cry:
    it always misses when i apply choke. it will also just miss when at steady rpm, no choke involved, i guess it must be sticking float?
    i know my description of the problem is vague, but the probems are bloody weird. it must be a couple things in combination.
    nice poke at the storm, but not all of us can have the luxury of EFI! :LOL:
    thanks again for the reply mate