I just bought a 98 wr400, its a bit older, but i wanted a project. Im powdercoating the frame and rebuilding the suspension, but while i have it apart.... what can i do in the engine? Ive heard of the timing, the grey wire and the throttle stop, ive got that. What about big bore kits, does anyone sell aftermarket hop up stuff for these yet (apart from exhaust)? Any help is appreciated, also, what would YOU improve on the engine?