Discussion in '2-Stroke Engines' started by 757bikes, Jul 6, 2016.

  1. 757bikes

    757bikes New Member

    So i installed my kit a couple days ago and it runs first try! Great! Except for the fact that the bike won't slow down but just go faster without any throttle. I have tried everything, There is no kink or anything wrong with the throttle, i have installed an O-ring in the carb, and I've even added sealant around the slits of the carb incase of an air leak, i am using an offset intake manifold but the bike still goes faster with the stock manifold. I don't know what to do at this point, the only way to slow down is if i ride the kill switch but thats the only way it'll slow down and I can't Idle it cause of how high it will end up reving. Please help I will do anything at this point.

  2. Frankfort MB's

    Frankfort MB's Well-Known Member

    You have an air leak somewhere. Most likely intake gasket or base gasket
  3. 757bikes

    757bikes New Member

    the thing is tight as steel i don't see it being there.
  4. Frankfort MB's

    Frankfort MB's Well-Known Member

    Just because your bolts are tight doesn't mean your gasket isn't messed up
    agrmodz likes this.
  5. crassius

    crassius Well-Known Member

    spray around the intake with a spray bottle full of water - it should show a leak if there is one
  6. Randall

    Randall Member

    I had the same problem a while back and found out I had turned the throttle barrel 180 degrees. Check your throttle barrel.

    The barrel is the part the needle goes through.

  7. What Randall said. Except that video doesn't sell home what is arguably the most important point to make in replacing this assembly in the carb.

    I just finally got my first motorized bike build to work tonight. It took a while to get the thing started, for various reasons, but I was wondering why I could only adjust speed by adjusting the choke. The throttle did nothing.

    If you think about it, this problem implies that you are already getting maximum fuel and air, and are simply modifying the air:fuel ratio by opening the choke to let in more air.

    I realized there is a small notch in the throttle barrel. This notch must be aligned with the idle screw. If it is not, the idle screw simply prevents the entire throttle barrel from sitting down flush within the carb.

    That is, as Randall said, rotate your throttle barrel until you see that notch line up with the idle screw. It actually helps to turn in the screw to prevent it from seating in unless it is in the proper orientation. Make sure it sits down flush, tighten everything back up, and have a go.

    If you had the same problem as me, this will fix your issue, but create the new one of not having a good balance. You'll need to let out the idle screw and adjust the nuts at the top of the throttle barrel and at the throttle handle itself, until you have the appropriate amount of slack/tension so that the bike idles well.

    What might help is to put a fair amount of tension on the throttle cable, and to open the idle screw most of the way (counter clockwise). Then get the bike going, engage the clutch, and adjust the idle screw back in until it idles at a good rhythm.

    Hooe this helps! A lot of blood, sweat, and, well, cursing, went into figuring this out for my first time!
  8. JaredL

    JaredL New Member