Yamaha R15 2022 Service Manual page 263

Valve spring compressor
YSST-603
(90890-04019)
Valve spring compressor attach-
ment
YSST-603 A
(90890-04109)
5. To secure the valve cotters onto the valve
stem, lightly tap the valve tip with a soft-face
hammer.
ECA13800
Hitting the valve tip with excessive force
could damage the valve.
VALVES AND VALVE SPRINGS
5-26
ENG