TGB Blade 250 ATV Quad Service Repair Manual, Page 72Get this manual
6CYLINDER HEADNALVE
Valve guide Caution
Before measuring the valve guide, clean carbon deposits with reamerTool: 5.0 mm valve guide reamer
Measure and record each valve guide inner diametersService limit: 5.03 mm The difference that the inner diameter of valve guide deducts the outer diameter of valve stem is the clearance between the valve stem and valve guideService Limit: IN+O.08 mm EX+O.10 mm