Let me say that my FMF Q, while making a difference, was the worst bang-for-the-buck mod I did in the early stages of tweaking my bike. The stock exhaust just isn't a huge limiting for the stock motor. It also isn't that much lighter, like barley any. Save your cash, mod your stock pipe, get a 600R exhaust,and buy a CW cam, piston or CCW combustion chamber. I know people love exhausts, but in my experience the dividends were small for the investment with this bike.