Yamaha YZ 2023 Series, Owner'S Service Manual

Page: 257 / 378

CRANKSHAFT AND BALANCER SHAFT
5-70
EAM30491
REMOVING THE CRANKSHAFT
1. Remove:
•
Balancer shaft “1”
TIP
Remove the balancer shaft with its flat side “a”
facing the crankshaft.
2. Remove:
•
Crankshaft assembly “1”
TIP
Remove the crankshaft assembly by using the
crankcase separating tool “2”.
EAM30492
CHECKING THE CRANKSHAFT
1. Measure:
• Crankshaft runout “a”
Out of specification

Replace the crank-
shaft.
TIP
Turn the crankshaft slowly.
2. Measure:
•
Crank assembly width “a”
Out of specification

Replace the crank-
shaft.
3. Check:
• Crankshaft sprocket “1”
Damage

Replace the crankshaft.
4. Check:
•
Crankshaft journal oil passage
Obstruction

Blow out with compressed air.
Crankcase separating tool
90890-04152
Crankcase separating tool
YU-A9642
1
a a
2
1
Runout limit
0.030 mm (0.0012 in)
Crank assembly width
55.93–56.00 mm (2.202–2.205 in)
a a
1