I'm planing on using a OS FS-70 surpass, or a OS FS-91 surpass, so need info on those two, how do I set the valves (or adj) how often do I replace the valves, cam, rockers, and on a 2-stroke engine the fuel/oil go through the crank, and case the lube the inside of the engine, so where dose the oil come from to lube a 4-stroke?

Can you rotate the carb on these engines?

I'm running a 13/62 gearing right now =4.76 gear ratio and I'm planing on running a 21/48 gearing which =2.28 dose that sound ok?

sorry for asking so many qusetions, I'm trying to get a hold of the guy with the revo, but I don't know how too.