Yamaha PZ50W Service Manual page 209

VALVES AND VALVE SPRINGS
5. To secure the valve cotters onto the valve stem,
lightly tap the valve tip with a soft-face hammer.
CAUTION:
Hitting the valve tip with excessive force could
damage the valve.
6. Lubricate:
• Valve pad
• Valve lifter
(with the recommended lubricant)
7. Install:
• Valve pad
• Valve lifter
NOTE:
• The valve lifter must move smoothly when rotated
with a finger.
• Each valve lifter and valve pad must be rein-
stalled in its original position.
5-40
ENG
Recommended lubricant:
Molybdenum disulfide oil