SANYANG INDUSTRY CO. XS125-K Service Manual page 45

5. CYLINDER HEAD/ VALVE
VALVE SEAT INSPECTION/ REFACING
Clean intake and exhaust valves to remove carbon
deposits.
Apply a light coating of prussian blue to each valve
face.
Insert each valve into the guide and rotate them two
cycles.
Remove the valve and inspect the face.
CAUTION:
If the valve face is burned or damaged or unevenly,
replace the valve.
Inspect the valve seat.
If the seat is too wide or too narrow, the seat must be
refinished.
CONTACT AREA
SERVICE LIMIT
1.5mm
VALVE SEAT
SERVICE LIMIT
1.8mm
5-9