engine surges at full throttle

Discussion in '2-Stroke Engines' started by boss4457, Aug 3, 2015.

  1. boss4457

    boss4457 New Member

    my engines surges at full throttle like it goes to higher rpm then back down then back up im wondering if any body can help

  2. jaguar

    jaguar Well-Known Member

    air leak, intake or head.
    seal the carb/manifold connection and resurface the head on sandpaper on glass.
    if it has a bunch of miles on it then it could be a crank seal leak.
  3. crassius

    crassius Well-Known Member

    could also be running out of fuel at that speed - check fuel flow and check that vibration isn't making your fuel foam in the bowl
  4. jaguar

    jaguar Well-Known Member

    that's true. a well used bike could have crap clogging the in-tank fuel filter.
    pull the fuel line off the carb and turn the fuel petcock on. there should be a healthy flow there.
    also make sure your fuel tank is breathing. if the problem goes away by taking the cap off then you'll need to drill a hole into it to let the tank breath (incoming air takes the place of the gas that went to the carb. otherwise a vacuum happens which prevents fuel flow.)