Hi all, I just picked up a modded RM-Z250 with a higher compression piston, stainless valves, valve springs, and a cam. The guy I bought it from said to run 100 octane (per the engine builder). They ran half and half race gas (either U4 or EV, not sure which). There is a Union 76 station near my work that sells 100 octane unleaded Sunoco GT 100 out of the pump. Obviously it would be much cheaper (and convenient) for me to run the 100 octane pump gas since it is only aroud $5/gallon. I'm trying to get in touch with the engine builder to get his opinion, but in the mean time, I WANT TO RIDE! What do you guys think: good, bad, no difference, engine's gonna blow instantly, what?