Hi Guys! I was checking out the top end of my new used bike today 92 KDX 200, cleaning the piston etc. And when I took out the left valve exhaust part 12005 in the pic provided. The bottom of the gear looks all chewed up. Does anyone know what would cause it to grind up? Cause i'm going to order some parts but don't want to take every thing apart until I can get a manual. Thanks for any help!
http://home.cogeco.ca/~lleepp/convert.png
http://home.cogeco.ca/~lleepp/convert.png