Removing The Balancer Shaft; Removing The Crankshaft Assembly; Checking The Crankshaft Assembly - Yamaha YZ450FX 2019 Owner's Service Manual

CRANKSHAFT ASSEMBLY AND BALANCER SHAFT
EAM30143

REMOVING THE BALANCER SHAFT

1. Remove:
• Balancer shaft "1"
TIP
Remove the balancer shaft with its flat side "a"
facing the crankshaft.
EAM30144

REMOVING THE CRANKSHAFT ASSEMBLY

1. Remove:
• Crankshaft assembly "1"
TIP
Remove the crankshaft assembly by using the
crankcase separating tool "2".
Crankcase separating tool
90890-04152
Crankcase separating tool
YU-A9642
1
EAM30145

CHECKING THE CRANKSHAFT ASSEMBLY

1. Measure:
• Crankshaft runout
Out of specification  Replace the crank-
shaft, bearing or both.
TIP
Turn the crankshaft slowly.
1
a
2. Measure:
• Crank assembly width "a"
Out of specification  Replace the crank-
shaft.
2
3. Check:
• Crankshaft sprocket "1"
Damage  Replace the crankshaft.
5-68
Runout limit
0.030 mm (0.0012 in)
Crank assembly width
61.93–62.00 mm (2.438–2.441 in)
1