Bike runs while idling.

Discussion in 'Frame Mounted Engines' started by Ryno, Aug 17, 2011.

  1. Ryno

    Ryno Member

    There is a laundry list of things wrong with my bike at this point, but I'm trying to take it one thing at a time. The thing that I'm trying to figure out is:

    Why does my bike start to accellerate when I'm not even pulling the throttle? Is this a problem with the throttle or with the carb? The only way that I can get a sufficient amount of acceleration is by not pulling the throttle at all... I'm confused.

    Here are the current (unrelated) problems with my bike:
    Kill switch doesn't work (button is broken, and the electrical stuff didn't work before either)

    The reducer ring in the carb is broken, I'm using a makeshift one out of rubber because I don't know the size of the ring to order a new one

    The carb is constantly tipping over because it's not a good enough fit on the makeshift ring.

  2. Ryno

    Ryno Member

    Also, when the engine is running and I pull the clutch, the engine revs up really fast as if I was pulling the throttle while the clutch was engaged.
  3. Al.Fisherman

    Al.Fisherman Active Member

    Term is clutch is DISENGAGED. If the clutch is engaged, the engine would most likely stall out.

    Boy that was simple.
    Last edited: Aug 17, 2011
  4. Ryno

    Ryno Member

    I meant the electrical elements of the kill switch only.

    And what should I do about this "Vaccum Leak" situation?
  5. Ryno

    Ryno Member

    I'm sorry that I'm not an expert on terminology and motored bikes. if I was, the chances are I wouldn't be here asking for help.
  6. Al.Fisherman

    Al.Fisherman Active Member

    First of all you NEED to fix the mounting on the carburetor, I KNOW it's leaking there.

    Places of possible leaks.
    1. Carburetor/intake gasket
    2. Seals
    3. Cylinder to base gasket
    4. Case to case gasket.
    Last edited: Aug 17, 2011
  7. Ryno

    Ryno Member

    Ok thanks. This is something I've been struggling with... how should I measure out the nylon piece? The sizes are confusing and I don't even know what to measure it with/how to measure it.

    Not to mention that the piece that I have is broken and thinned out anyway.
    Last edited: Aug 17, 2011
  8. Al.Fisherman

    Al.Fisherman Active Member

    Truly un (@@@@@@@)....believable. Truthfully, I think you need to sell your bike.
    Last edited: Aug 17, 2011
  9. Ryno

    Ryno Member

    Well that was awful rude. I appreciate the help that you've provided to me but if you are just going to be arrogant and abusive then stay out of my threads.
  10. ddesens

    ddesens Member

    Post a Picture. It would help us help you. Sounds like you need a new intake tube. Make sure you have the slide in the carb inserted in the correct position.
  11. sparky

    sparky Active Member

    I saw nobody mention the idle screw....

    But it *is* likely going to be an air leak.

    Just take the carb off. Then take the intake manifold off.

    You should see the "walls" of the manifold and carb should be mostly dry. Perhaps there is a thin ring of gas... but if you see gas all over one of those "walls", then you've got an air leak.


    as far as the kill switch goes, all it does is ground out the motor so... first of all the installation manuals tell you to match wires that don't match and connect the ground wire to the bike with no paint blah blah blah.BS. since there's no true power running through the kill switch and all it does is touch the wires, connect one wire to the positve coming out the engine(not the white one like the manual says, you'll leave it open for a headlight or something), and connct the other wire from the killswitch to the ground. doesn't matter what color from the switch! if its not working after that take off your throttle, open it up and look at the button from the back side, ones most likely ripped off. If so order a new one OR do what i did and ordered a soldering tool from chyna on ebay for like $3 and solder it back together. presto... working kill switch.

    and for the acceleration try turning the screw on the carb(left of the tickle button, left side of bike) turning it to the left.(also try what the others said by changing gaskets and all. your kit should've came with extras or you can order them at or boygofast on ebay. also check EVERYTHING that might have an air leak, like loook where your carbs mounted, it might just need to be pushed in more and tightend. but you might want a whole new carb to start with. boygofast is highly suggested to get it from(by me). don't forget to prime your new carb.

    and it revs up with the clutch disengaged because of the air leak, when you pull the lever nothing holds the motor back so it goes.

    sorry to drag it on. I hope you get it fixed ang get back on the road again.
  13. SdCruizer

    SdCruizer Member

    you can get cheap plastic CALIPERS from harbor freight or any tool store
    or a decent digital set
    you clamp it on the part your measuring and it can tell you in mm, inches what the size is
    then look up online or at a parts store for that size mm, or inches
  14. HeadSmess

    HeadSmess Well-Known Member

    omg...calipers? :eek:

    dial, vernier or digital?

    metric or imperial?

    omg, the mind boggles! :p

    or you could buy my super accurate 1/10,000" twiddler gauge for a few hundred dollars if you require super accurate answers :)

    once a carb needs an adaptor ring to fit onto a manifold...the carbs too big or the manifolds too small. i dont care if they sell them like that.

    why cant people tell the difference between 10mm and 10.5mm?