My ryobi ,bowman ring, 140 timing, thinner gasket, ignition module and wt540 carby, slots in cylinder turned a 18 x 8 @7400 but the 12 dia carby gave problems with the idle and the high speed needle dropped out as it was wound out that far to make it run.
I went back to the wt526 carby and the 18 x 8 gave me 6800 rpm but hunted between 6400 and 6800 and I could not get it to run at top speed without hunting. Idle was 1400 rpm and smooth.
I was not happy with the level of vibration either, in a plane it would shake the servos to pieces. Can a ryobi conversion be expected to run with vibration levels compariable to glow engines or am I "dreaming" .
Do you have to use rubber mounts on the stand-offs or is it better to bolt to a solid ply firewall?
Has anyone got a video of a ryobi at full power to demonstrate the level of vibration you can expect.