I rode a comrade's WR426 and he rode my YZF426 this past weekend--both 02's. His launched like a rocket on the low end when twisted...mine comes out pretty slow but has an incredible mid and high range hit that his does not. He said his gearing in the back is actually about 7 teeth smaller than WR stock with stock motor. I would think this would wipe out his low end. Mine is YZF stock gearing and only added PowerNow. I do not have the legendary bog problem. I love the bike but in the tight stuff it is a lugger. Besides, "shoulda bought a WR," is there something I might be overlooking? Oh he did mention that from the outside cover it looked like someone had possibly been in there at the timing and maybe it was set up differently. I think the previous owner did some MX.