2009 Polaris Scrambler 500 4x4 2x4 factory service manual, Page 75Get this manual
ENGINE S If the contact area of the cutter is in the same place, the valve guide is distorted from improper installation and must be replacedBe sure the cylinder head is at the proper temperature and replace the guideIf the contact area of the initial cut is greater than 75, continue to cut the seat until all pits are removed and new seat surface is evidentNOTE: Remove only the amount of material necessary to repair the seat surface
Valve Seat Width: Intake Std: .028 (.7 mm) Limit: .055 (1.4 mm) Exhaust Std: .039 (1.0 mm) Limit: .071 (1.8 mm)