1984 Official Honda TRX200 Shop Manual, Page 71Get this manual
CYLIND ER HEADIVALV ES
Use 45 degree cutte to remove any roughness or irregularities from the seat
Reface the seat with 45 degree cutter when the valve guide is replacedUse 32 degree cutter to remove 114 of the exist ing valve seat material
Use 60 degree cutter to remove the lower 14 of the ld seatRemove he cutter and inspect the area you have just cut