After 3,5 years opened engine, working normally, noticed this eaten up gears. Its 4th gear in a '99 WR When I bought the bike, 3rd and 4th gear were just replaced. Did 5000 miles max since. this gear had only one tooth eaten its co-working brother gear looked like this and thats a new one, wating to turn fast. Some say 3 in 4 gear are the weak points of wr's, think I avoided disaster of broken gears, what already happened to this bike once.