Yamaha YZ250F(R) Owner's Service Manual page 196

VALVE CLEARANCE INSPECTION AND ADJUSTMENT
3. Remove:
Right radiator
G
Refer to "RADIATOR" section in the
CHAPTER 4.
Carburetor
G
Refer to "CARBURETOR" section in
the CHAPTER 4.
Spark plug
G
Upper engine bracket
G
Cylinder head cover
G
Refer to "CAMSHAFTS" section in the
CHAPTER 4.
4. Remove:
Timing mark accessing screw 1
G
Crankshaft end accessing screw 2
G
O-ring
G
5. Check:
Valve clearance
G
Out of specification → Adjust.
Valve clearance (cold):
Intake valve:
0.10 ~ 0.15 mm (0.0039 ~ 0.0059 in)
Exhaust valve:
0.17 ~ 0.22 mm (0.0067 ~ 0.0087 in)
3 - 19
INSP
ADJ