Keihin vs. Mikuni? They are just 2 different companies. Both work well. For instance, All 70's Kawasaki's came with Mikuni's. Honda's came with Keihin's. Mikuni's seem to be anjoying a celebrity status around here. If interesetd, check out some of the Keihin performance carbs. Either way, if you have a stock bike, the money's better spent on other mods like a cam/springs/pistons/exhaust. After these are done, a larger carb WILL make a difference.