Yamaha YZ250F(E), Owner'S Service Manual

Page: 260 / 356

CRANKSHAFT ASSEMBLY AND BALANCER SHAFT
5-67
EAS1SM1285
REMOVING THE CRANKSHAFT ASSEMBLY
1. Remove:
• Crankshaft assembly “1”
TIP
Remove the crankshaft assembly by using the
crankcase separating tool “2”.
EAS1SM1286 CHECKING THE CRANKSHAFT ASSEMBLY
1. Measure:
• Crankshaft runout
Out of specification

Replace the crank-
shaft, bearing or both.
TIP
Turn the crankshaft slowly.
2. Measure:
• Big end side clearance D “a”
Out of specification

Replace the big end
bearing, crankshaft pin, or connecting rod.
3. Measure:
• Crankshaft width A “a”
Out of specification

Replace the crank-
shaft.
4. Check:
• Crankshaft sprocket “1”
Damage

Replace the crankshaft.
5. Check:
• Crankshaft journal oil passage
Obstruction

Blow out with compressed
air.
Crankcase separating tool
90890-04152
YU-A9642
Runout limit C
0.030 mm (0.0012 in)
2
1
Big end side clearance D
0.150–0.450 mm (0.0059–0.0177
in)
Width A
55.95–56.00 mm (2.203–2.205 in)
1