I also have the new 09 YZ450F's and i want more bottom end for hair scrambles and GNCC races. The bike is all stock and i seem to stall the bike a little more then i have on any other bike i have ever had. Any information or ideas for more bottom end and tips anything to help prevent stalling. A fly wheel weight will help with the stalling, after market exhaust will really wake that bikes motor up. I have the 08 and the pipe REALLY made things exciting.