Just curious? I have understand you can not change the exhaust cam timing on the WR's w/auto decomp due to the pin length and the timing of when it opens the valve. What I am curious about is why you can make this mod to a YFZ in 04 and 05, which I have done many w/o issue and they still start very easy. It seems that a YFZ would suffer the same effect as the WR by advancing the cam. Has anyone determined the difference.