2005-2011 Honda Recon TRX250TE/TM service manual, Page 134Get this manual
CYLINDER HEADIVALVE Using 45" seat cuner, cut the seat to the proper
widthVALVE SEAT WIDTH1.2 mm (0.05 in)
1.2 mm (0.05 in)
Make sure all pining and irregularities are removed
Change the angle of lapping tool frequently to prevent uneven seat wearLeppmg compound