TGB Blade 250 ATV Quad Service Repair Manual, Page 74Get this manual
6CYLINDER HEADNALVE tir Servh Clean up cm carbon deposits urliu intake and exhaust valvesApply with emery slightly onto valve contact faceGrind valve seat with rubber hose or other manual grinding tool
Caution
and valve guideClean up the emery after corrected, and apply with engine oil onto contact faces of valve and valve seatRemove the valve and check its contact face
Caution
Replace the valve with new one if valve seal is roughness, wear out, or incomplete contacted with valve seatValve seat width