Im working on a UAV hybrid, and i have 2 engines with differing and confusing specs. My aim is to gear down the output to around 5000 RPM to match the alternator. The first engine, is a Kyosho GT 0.15Ci (2.5cc) rated at just under 0.5 Hp at 29,000 RPM so reduced to 5000 RPM should give me a theoretical 3 Hp or approx 2.2Kw..ish The other is an elderly MAX OS 40, ive not found out much data on…