A mate of mine has just bought a 1996 gasser JTR270 and we've noticed that it has a slapping sound coming from the engine, it sounds like the piston is slapping something but the bike has plenty of compression and plenty of power, it starts first kick every time and everything else seems fine. Anybody heard this before and can point us in the right direction?????????????????????

Come on, some1 must have seen this before?????????????

It's a 13 year old bike, could be anything to be honest.

Almost impossible to diagnose over the internet.

Hi scotty,

I would suggest a new piston kit from this info, I think these may only be available in A and B sizes, go for the B if available.

Bye, PeterB.