I have an 02 CR250 as well; to my knowledge our only choice is to drop 500+ on the madman eng. WR kit. There was talk about the possibility of using gears out of the 450x but I never had the $$ to look into it further. i have a gnarley pipe, flywheel weight, messed with the sprocket ratios and tried an intake spacer. they all worked ok but a WR gear set would be best.
If you find anything Cman, please post it up
Edit: looks like the MME WR kits are 780$ now :bang: