Valve Guide

Ream the valve guides for oversize valves if the clearance exceeds the specifications.
^ Intake clearance 0.0257 (0.001 inch) Max.
^ Exhaust clearance 0.0508 mm (0.002 inch) Max.

Valve seats should be concentric to within 0.05 mm (0.031 inch)

Replace the valve if the edge of the head is less than 0.79 mm (0.031 inch)