I was looking at the power up kit from XR's only, and was wondering if anyone has installed the 11:1 or 12:1 comp piston with a cam? and what else does the kit include besides piston and cam? my 650R engine is stock with simple intake and exhuast uncorking mods, and im looking to launch the power, and possible race it. I dont wanta give up reliability, so how have they held up for you guys that have them? XR's only says run race gas only in 11:1 and higher...but they also say 93 octane for the stock 650R, and it runs great on 87 so can you use regular 93 octane pump gas? Anybody have the kit with a big bore?