See entries under 'Strange Noise': I now anticipate its the power valve. It rocks slightly when lowered at tickover/low revs, so the metal slider clatters against the barrel chamber. This can be checked with front section of the exhust pipe removed, reach in to touch the bottom of the slider and att...

Twostrokes are typically noisy when engine spinning down from high revs. It's a buzzing rattle, not a knock. I noticed a metalic rattle, almost a sqeek like a chain without any oil when slowing down in gear with a VERY loose chain! It was where the chain rides off the front dive cog slightly. This i...

I now anticipate its the power valve. It rocks slightly when lowered at tickover/low revs, so the metal slider clatters against the slider wall. This can be checked with front section of the exhust pipe removed, reach in to touch the bottom of the slider and attempt to rock the slider with your fing...

I've bought my CRM MK2 last year. At tidy, very low mileage example. Only this year it started that low/mid-range noise. Prior to this it ran clean as a whistle at any revs or throttle opening. Something has changed. I've adjust mixture,power valve (which operates well), air filter , spark plug and ...