have a s2 which had full engine rebuild about 6000 miles ago. recently started smoking etc. and compression was down on 1 cylinder.

Fault found to be cracked piston, it has cracked just below the first compression ring. Why could this be? the pistons are not genuine, they are patten parts - running 16psi. My mate has standard pistons with same setup and he hasnt had any probs. Could it b wrongs plugs or running lean or something?

Nxt question, thinkin of putting some 17" alloys on, has been lowered about 30mm on koni's. Will they catch or will lots of mods on the arch's be required?