Yamaha YZ125X 2022 Owner's Service Manual page 173

3. Install:
• Piston "1"
• Piston pin "2"
• Piston pin clip "3"
New
TIP
• Apply engine oil the piston pin.
• Make sure the arrow mark "a" on the piston
points towards the exhaust side of the cylinder.
• Before installing the piston pin clip, cover the
crankcase opening with a clean rag to prevent
the clip from falling into the crankcase.
• Do not allow the clip open ends to meet the pis-
ton pin slit "b".
4. Lubricate:
• Piston
• Piston ring
• Cylinder
(with the recommended lubricant)
Recommended lubricant
Engine oil
CYLINDER HEAD, CYLINDER AND PISTON
5. Install:
• Cylinder
• Cylinder nut "1"
TIP
• While compressing the piston ring with one
hand, install the cylinder with the other hand.
• Tighten the nuts in stage, using a crisscross
pattern.
6. Install:
• Collar "1"
• Push rod "2"
• Plain washer "3"
• Push rod bolt "4"
ECA27100
NOTICE
Be sure to use the collar. If the collar is not
used, the power valve constituent parts will
result in damage.
TIP
• Insert the collar "5" included in owner's tool kit
to install the push rod bolt.
• Do not forget to remove the collar.
5-13
Cylinder nut
30 N·m (3.0 kgf·m, 22 lb·ft)
Push rod bolt
4.5 N·m (0.45 kgf·m, 3.3 lb·ft)