Hey, I have been building for a bit now, some may have seen pics of my newest build I just posted on the cruiser forum. But I have always built cruisers and always used grubee gt5's. But now I think I want to build a mountain bike for trail riding. My question is, does a 4 stroke offer better low end power? I know nothing about 4 stroke motors. I was looking at the 49cc from deamon bikes. Aside from reliability and not mixing your oil, what benefits does a 4 stroke offer? Can I expect more power or speed from a 49cc 4stroker? also what does anyone think about fitting this thing to a bike? AUTO 125CC 4-STROKE ENGINE MOTOR ATV GO KART DIRT BIKE - eBay (item 150565213084 end time Feb-28-11 02:13:27 PST)