Engine Trouble Engine Is Jerky At Low Speed

Discussion in '2-Stroke Engines' started by cosworth, Apr 12, 2013.

  1. cosworth

    cosworth Member

    I've got about 50 miles on my new motor and thought the engine would smooth out by now. Problem is that between 12-15 mph (approximately) the engine jerks. It isn't until it get over that range does it smooth out - some what. I've read the forum and have looked for a cure (i.e. O ring in the carb to seal out air, check all gaskets, tighten all nuts, played with needle positioning, went hotter and colder on the plug, went to a heavy duty chain with CNC machined sprocket and hub drive etc. I'm open to any and all suggestions

    Attached Files:

  2. crassius

    crassius Well-Known Member

    kind of a general problem with 2-strokes - power isn't steady all across the throttle range

    you're kinda stuck with big sprocket for low speed smoothness or smaller sprocket for top speed

    other option is to go with a shift kit
  3. jaguar

    jaguar Well-Known Member

    jerky? sounds like a clutch problem.
  4. cosworth

    cosworth Member

    I appreciate you input. If I had done more research, or knew about the forum before hand, I would have gone with a shifter kit.
    Thanks again for your time.
  5. Samdallas214

    Samdallas214 Member

    My did the same thing jerked at low speed and stopped at higher speeds.
    In my case the engine was bran new less then 25 miles on it but it had a broken clutch spring
  6. Fabian

    Fabian Well-Known Member

    It's never too late to get a shift kit - best thing since sliced bread
  7. cosworth

    cosworth Member

    Thanks for your input. Clutch seems fine and engine doesn't cut out but I'll check it.