I just purchased an 08 YZ450F. I keep hearing how slow it is. I was riding an '06 YZ450F and was using most of it. I haven't even ridden the 08 yet, but am concerned. I guess I will need to get a pipe, power bowl, gearing to start with. Is it true that the 06 was the fastest of the three? Main question?..... Anybody currently riding an 08 that was riding an 06? How much difference is there really.