Yamaha YZ450FF 1SL-28199-11 Owner's Service Manual page 254

NOTICE
After tightening the bolts, make sure that
the oil pump turns smoothly.
2. Install:
• Balancer weight gear "1"
TIP
Install the balancer weight gear and balancer
shaft with their lower splines "a" aligning with
each other.
3. Install:
• Balancer drive gear "1"
TIP
• Align the punched mark "a" on the balancer
drive gear with the punched mark "b" on the
balancer weight gear.
• Install the balancer drive gear and crankshaft
with the lower splines "c" aligning with each
other.
4. Install:
• Lock washer "1"
New
• Balancer weight gear nut "2"
Balancer weight gear nut
50 Nm (5.0 m·kgf, 36 ft·lbf)
• Primary drive gear "3"
• Conical washer "4"
New
• Primary drive gear nut "5"
Primary drive gear nut
100 Nm (10 m·kgf, 72 ft·lbf)
OIL PUMP AND BALANCER GEAR
• Straight key "6"
• Balancer "7"
• Lock washer "8"
• Balancer nut "9"
Balancer nut
45 Nm (4.5 m·kgf, 33 ft·lbf)
TIP
• Apply engine oil to the contact surface and
threaded portion of the primary drive gear nut.
• Apply engine oil to the contact surfaces of the
conical washer.
• Place an aluminum plate "a" between the
teeth of the balancer drive gear "10" and bal-
ancer weight gear "11".
• Install the conical washer with its convex sur-
face "b" outward.
10
5
4
10
3
5. Bend the lock washer tab.
5-59
New
1
11
2
a
11
a
3
b