throttle/idle issue

Discussion in '2-Stroke Engines' started by ecgoeken, Jan 2, 2010.

  1. ecgoeken

    ecgoeken New Member

    ive been having some problems when idling. when i take my bike out of gear the slightest twist of the throttle will make the bike rev into really high rpms. one time i thought the motor was going to blow. on the other hand it wont idle without giving it gas. ive tried to adjust the idling speed by twisting the little screw and have got it to idle but then after a short ride it was back to its strange behavior. the carb seems to be attatched tightly as well. does anyone know what might be causing this? im not sure whats going on with it but i hope its an easy/cheap fix.

  2. EnFlaMEd

    EnFlaMEd Member

    Sounds like an air leak to me. I would check...

    -Jug to intake manifold gasket (replace/silicone)
    -intake manifold to carb sealing (o-ring and silicone if possible)
    -top cap of carb sealing (you can o-ring this as well)

    Grab some "start ya *******/aerostart" or similar product and spray around those areas. If your idle changes then you have found a potential air leak.
  3. give me vtec

    give me vtec Active Member

    with these engines its almost always a cheap easy fix... do you have an o-ring between the carb and intake tube?

    second... i dont think you can blow these engines that easy. I put nos on my engine a couple times and revved CRAZY high... i mean twice as high as i had ever gotten an ht. It still runs fine. As long as you have good lube these engines are surprisingly durable... at least the good ones are.
  4. ecgoeken

    ecgoeken New Member

    no, i dont have any o-rings on it, so that could be the issue. basically all i have on it at the moment is whatever came in the box. i'll try to seal up between all the possible places air could be leaking between the carb and motor. also, i dont know if this makes a difference but the day it started acting up i was running at top speed for a long ride (maybe a half hour at the most at top speed).
  5. give me vtec

    give me vtec Active Member

    get the o-ring from sick bike parts....
  6. ecgoeken

    ecgoeken New Member

    any suggestions on the kind of o-rings i should use. and also what are the terms ur using. ex. "jug" "intake mainfold to carb sealing" "top cap of carb". i know there is a tube coming from the motor and then the carb is attatched to the tube with a clamping ring. sorry, im not familier with the jargon yet.
  7. EnFlaMEd

    EnFlaMEd Member

    Intake manifold would be the tube you describe.

    The jug is the part of the engine the intake manifold is connected to.

    On top of the carb there is a cap which can screw off. The throttle cable comes in through this and when you unscrew it and pull it out the needle and slide assembly is all attached to it. sell the o-ring you need. You can use one where the carby meets the manifold and also the same sized one under the carb cap I have just described.

    With my engine I couldn't get a proper seal even with the o-rings in place so I also used a lot of copper RTV (silicone) to get it sealed properly and now my engine is fine.

  8. Catfishjohn

    Catfishjohn New Member

    Check out this thread.
    Motorbike Wanabe was working on my engine and the procedures mentioned by him and others on this thread seemed to help my engine to run better. I'm waiting now for my break-in to be completed so I can fine tune.
  9. ecgoeken

    ecgoeken New Member

    nice, that makes sense. thanks for clearing that up. i'll order those o-rings and see if that takes care of the problem.
  10. AussieSteve

    AussieSteve Active Member

    Last edited: Jan 2, 2010