Pinning the piston, grinding out the exhaust port bridge, and using a new Frank Bowman ring are the FIRST things I do when doing a Homelite 25cc.

The ring gap on these little engines should be really, really tight. Spec. is .003" for the ring gap, and that is about the thickness of a sheet of paper. I'll bet if you check, your ring gap is several times that big.

Hop ups go like this:

1. Make the engine like new in all sealing, including ring.
2. Then start modifying other things.

Always start with a freshened engine, never with something that could gain power just by a simple overhaul. The new ring is only like 10 bucks...

AV8TOR