Yamaha WR250F 2022 Owner's Service Manual page 237

1 1
E
3. Lubricate:
• Piston
• Piston ring
• Cylinder
4. Offset:
• Piston ring end gap
a
15
15
d
c
a. Top ring
b. Upper oil ring rail
c. Oil ring expander
d. Lower oil ring rail
5. Install:
• Gasket
New
• Dowel pin
• Cylinder
Cylinder bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
TIP
• While compressing the piston rings with one
hand, install the cylinder with the other hand.
• Pass the timing chain and timing chain guide
a a
E
3 3
2 2
3
15
b
5-36
CYLINDER AND PISTON
(exhaust side) through the timing chain cavity.