I've started thinking that too but i looked at the piston on both sides and they're not too bad. Rings move freely, no sign of cracks. The carby now leaks badly and it seems to be leaking where the gasket is. I've replaced the gasket, lapped each half of the carby, changed the o-ring in the jet, ensured that the spindle does not foul the other half of the carby. This leaves the float/needle which seemed to work outside the carby. Spark plug i think is too damp as well, stick it in spark plug hole, no priming and is still pretty damp. I'm ready to give up
