I've got a 2004 peugeot jet force 50cc (injection model). I tried starting it one day and it wouldn't rev then cut out after about 2 mins. To start it again i would need to clean the spark plug but still it wont rev. I've since found a split in the head gasket and replaced that, but still no joy ???

david, February 2009

Possibles:blocked exhaust, head gasket incorrect / mating surfaces not perfect (check with steel rule & thinest feeler guague), throttle cable stretched (renew), dirty fuel [clean all lines, tank, renew filter(s)], renew spark plug. Can anything affect the timing? Clean all earths. Start with easiest task. Make checklist.
All the best!

Nortim, February 2009