Yamaha WR250F 2021 - Page 237

CYLINDER AND PISTON
5-37
3. Lubricate:
• Piston
• Piston ring
• Cylinder
4. Offset:
• Piston ring end gap
5. Install:
• Gasket
• Dowel pin
• Cylinder
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.
a. Top ring
b. Upper oil ring rail
c. Oil ring expander
d. Lower oil ring rail
Cylinder bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
1
3
3
2
2
a
a
E
E
3
a
db
c
15
15
15
New
T
R
.
.