Yamaha YZ450FX 2019 Owner's Service Manual page 234

clip from falling into the crankcase.
• Make sure that the end of the piston pin clip is
not positioned at the cutout in the piston.
a
1
2
3. Lubricate:
• Piston
• Piston ring
• Cylinder
4. Offset:
• Piston ring end gap
a
15
d
15
15
e
a. Top ring
b. 2nd ring
c. Upper oil ring rail
d. Oil ring expander
e. Lower oil ring rail
5. Install:
• Cylinder gasket
New
• Dowel pin
• Cylinder
Cylinder bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
3
3
c
15
15
b
5-35
CYLINDER AND PISTON
TIP
• While compressing the piston rings with one
hand, install the cylinder with the other hand.
• Pass the timing chain and timing chain guide
(exhaust side) through the timing chain cavity.