i bought a 02 yz 426 two months ago. what a pig. i could not figure out why it was not as responsive as my Friends 00. after reading a thread regarding flywheel wait kits last night, i pulled the one that was on mine off. what a difference she has come to life. the throttle respose is crisp. it should be a major improvement when i ride it tomorrow. i just tormented the neighbors with a couple hot lapps today.