Engine Trouble 0 to 34 kph no worries then just coughing and spluttering

Discussion in '2-Stroke Engines' started by jimi076, Sep 2, 2012.

  1. jimi076

    jimi076 New Member

    Hay guys, have just finished run in and my bike rides like a dream from 0-34 kph but then you can hear the motor has more to give (i actually had it up to 50 kph a couple of times) but then it just starts coughing and spluttering and refuses to speed up. I am not running any fuel filter atm and was wondering if that could be causing the bikes "asthma attacks"? Cheers to all n advance, jimi

    Attached Files:

  2. crassius

    crassius Well-Known Member

    Had a new engine like that about a month ago. At high rpms it acted like the spark was breaking down, or the gas was foaming in the carb or something like that. Checked seals and all the usual stuff, but saw nothing wrong. Ran it a couple days hoping I'd spot something and started to notice some road dust sticking to the cases at the joint above the front motor mount. Not a leak, but just enough dampness to get the dust to stick. Pulled the clutch and tightened all case bolts with a hand impact, replaced clutch and all was well. I'm now assuming that the problem was that the case was leaking somewhere just enough to interfere with the high rpms.