Hey bdstr, I was digging thru my shed and found a 4-stroke Ryobi that I'd stripped down a few years ago. So I'm here right now looking for information and mounts and parts,etc.

But I do have a tip for you that I'd heard once that may increase the power for you.

As per EPA regulations, fresh air has to be mixed with the exhaust (or vis-versa) to get these little engines to pass smog . Anyway if you pull your carb and your exhaust header off and look very carefully against a bright light thru the ports, you may see a bleeder hole connecting the intake port and the exhaust port. There was one on my engine and I plugged it with JB weld. This mod is supposed to keep the exhaust fumes from "watering" down the fresh intake air. I got distracted before I had a chance to finish the engine conversion and see if my mod worked.