1983-1985 Original Honda ATC 200X Shop Manual, Page 65Get this manual
CYLINDER HEADVALVES
If the contact area is too low on the valve, the seat must be raised using 60 degree cutter
CaNT ACT TOO LOW
OLD SEAT WIDTH
Refinish the seat to specifications, using 45 degree finish cutterAfter cutting the seat, apply lapping compound to the valve face, and lap the valve using light pressureNOTE: Take care not to allow the compound to enter between the valve stem and guideAfter lapping, wash all residual compound off the cylinder head and valve