I recently purchased an RCV 120 that I mounted on a 60 scale Rare Bear. I have little experience with four stroke engines. I started the engine with factory setting and it ran fine except it got hot fast. It burned a hole in the exhaust deflector I had on it and damaged the fiber glass of the fuselage. I richened the low end considerably and got the engine running allitle cooler, however, the highest reading I get on my tachometer is around 524 RPM. The users manual is not very specific about setting up the engine, and I could use some help. I believe I have the low end set at around twelve turns out.</p>