Yamaha YZF-R1S Service Manual page 256

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. Install:
S valve pad 1
S valve lifter 2
NOTE:
S Lubricate the valve lifter and valve pad with
molybdenum disulfide oil.
S The valve lifter must move smoothly when ro-
tated with a finger.
S Each valve lifter and valve pad must be rein-
stalled in its original position.
5-34
ENG