YAMAHA YZ450F 2016 Owners Manual

FRONT FORK
4-47
24.Install:
• Damper assembly “1”
(to the inner tube “2”)
ECA32D1010
NOTICE
Allow the damper assembly to slide slowly
down the inner tube until it contacts the bot-
tom of the inner tube. Be careful not to dam-
age the inner tube.
25.Loosen:
• Rebound damping force adjuster “1”
TIP
• Before loosening the damping force adjuster,
record the setting position.
• Unless the damping force adjuster is fully
loosened, correct damping characteristic can-
not be obtained after installation.
26.Install:
• Damper adjusting rod “1”
• Copper washer “2”
• Adjuster “3”
(to the damper assembly “4”)
TIP
• While compressing the inner tube “5”, set the
cap bolt ring wrench “7” between the inner
tube and locknut “6”.
• Fully finger tighten the adjuster onto the
damper assembly.27.Measure:
• Gap “a” between the adjuster “1” and the
locknut “2”
Out of specification  Retighten and read-
just the locknut.
TIP
If it is installed with a gap out of specification,
correct damping force cannot be obtained.
28.Tighten:
• Adjuster (locknut) “1”
TIP
Hold the locknut “2” and tighten the adjuster.
Cap bolt ring wrench
90890-01501
YM-01501
1
2
1
New
Gap “a” between the adjuster and
the locknut
0.5–1.0 mm (0.02–0.04 in)
Adjuster (locknut)
29 Nm (2.9 m·kgf, 21 ft·lbf)
1
2a
T R..

FRONT FORK
4-48
29.Install:
• Adjuster “1”
(to the inner tube)
30.Fill:
• Front fork leg
ECA14210
NOTICE
• Be sure to use the recommended oil. Other
oils may have an adverse effect on front
fork performance.
• When disassembling and assembling the
front fork leg, do not allow any foreign ma-
terial to enter the front fork.31.Install:
• Damper assembly “1”
(to the outer tube)
TIP
Temporarily tighten the damper assembly.
32.Install:
• Protector guide “1”
EASB111169INSTALLING THE FRONT FORK LEGS
1. Install:
• Front fork “1”
TIP
• Temporarily tighten the pinch bolts (lower
bracket).
• Do not tighten the pinch bolts (upper bracket)
yet. Adjuster
55 Nm (5.5 m·kgf, 40 ft·lbf)
LOCTITE®
Recommended oil
Suspension oil S1
Standard oil amount
315 cm
3 (10.65 US oz, 11.11 lmp
oz)
Extent of adjustment
300–365 cm
3 (10.14–12.34 US
oz, 10.58–12.87 lmp oz)
T R..
1LT
1

FRONT FORK
4-49
2. Tighten:
• Damper assembly “1”
TIP
Use the cap bolt ring wrench “2” to tighten the
damper assembly.
3. Adjust:
• Front fork top end “a”
4. Tighten:
• Pinch bolt (upper bracket) “1”
• Pinch bolt (lower bracket) “2”
EWA33DD044
WARNING
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
5. Install:
• Protector “1”
• Bolt (protector) “2”
6. Adjust:
• Rebound damping force
TIP
Turn in the damping adjuster “1” finger-tight
and then turn out to the originally set position. Damper assembly
30 Nm (3.0 m·kgf, 22 ft·lbf)
Cap bolt ring wrench
90890-01501
YM-01501
Front fork top end (standard) “a”
0 mm (0 in)
Upper bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
Lower bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
T R..
2
1
a
T R..
T R..
Bolt (protector)
5 Nm (0.5 m·kgf, 3.6 ft·lbf)
21
T R..
1
2
1

FRONT FORK
4-50
7. Adjust:
• Compression damping force
TIP
Turn in the damping adjuster “1” finger-tight
and then turn out to the originally set position.
1

STEERING HEAD
4-51
EASB111170
STEERING HEAD
Removing the lower bracket
Order Part name Q’ty Remarks
Refer to “CHECKING AND ADJUSTING
THE STEERING HEAD” on page 3-35.
Use a suitable stand to raise the front wheel
off the ground.
Number plate Refer to “GENERAL CHASSIS” on page 4-1.
Handlebar Refer to “HANDLEBAR” on page 4-32.
1 Front fender 1
2 Steering stem nut 1
3 Front fork leg (s) 2 Refer to “FRONT FORK” on page 4-38.
4 Upper bracket 1
5 Steering ring nut 1
6 Lower bracket 1
7 Bearing race cover 1
8 Upper bearing 1
9 Bearing (lower side) 1
10 Bearing races 2
For installation, reverse the removal proce-
dure.
2
4
5
7
3
1
6
8
9
10
LS
T
.R.
LS
LS
T
.R.21 Nm (2.1 mlbf) kgf, 15 ft
T
.R.9 Nm (0.9 mlbf) kgf, 6.5 ft
T
.R.21 Nm (2.1 mlbf) kgf, 15 ft
T
.R.10 Nm (1.0 mlbf) kgf, 7.2 ft
T
.R.145 Nm (14.5 mlbf) kgf, 105 ft
38 Nm (3.8 m
lbf) kgf, 27 ft
7 Nm (0.7 m
lbf) kgf, 5.1 ft
*
*

STEERING HEAD
4-52
EASB111171REMOVING THE LOWER BRACKET
1. Use a suitable stand to raise the front wheel
off the ground.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Remove:
• Rng nut “1”
TIP
Remove the ring nut with the steering nut
wrench “2”.
EWA
WARNING
Securely support the lower bracket so that
there is no danger of it falling.
EASB111172CHECKING THE STEERING HEAD
1. Wash with kerosene:
• Bearing
• Bearing races
2. Check:
• Bearing
• Bearing races
Damage/pitting  Replace.
3. Replace:
• Bearing
• Bearing races
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the bearing race from the steering
head pipe with a long rod “1” and a hammer.
b. Remove the bearing race from the lower
bracket with a chisel “2” and a hammer.
c. Install a new bearing race.
ECA
NOTICE
If the bearing race is not installed properly,
the steering head pipe could be damaged.
TIP
Always replace the bearing and the bearing
race as a set.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4. Check:
• Upper bracket
• Lower bracket
(along with the steering stem)
Bends/cracks/damage  Replace.
EASB111173INSTALLING THE STEERING HEAD
1. Install:
• Lower bearing “1”
TIP
Apply the lithium-soap-based grease on the
dust seal lip and bearing inner circumference. Steering nut wrench
90890-01403
Exhaust flange nut wrench
YU-A9472

STEERING HEAD
4-53
2. Install:
• Bearing races
• Upper bearing “1”
• Bearing race cover “2”
TIP
Apply the lithium-soap-based grease on the
bearing and bearing race cover lip.
3. Install:
• Lower bracket “1”
TIP
Apply the lithium-soap-based grease on the
bearing, the portion “a” and thread of the steer-
ing stem.
4. Install:
• Steering ring nut “1”
TIP
Install the steering nut with its stepped side “a”
facing downward.
Tighten the steering ring nut with a steering
nut wrench “2”.
Refer to “CHECKING AND ADJUSTING
THE STEERING HEAD” on page 3-35.5. Check the steering stem by turning this lock
to lock. If there is any binding, remove the
steering stem and check the steering bear-
ing.
6. Install:
• Washer “1”
7. Install:
• Front fork “1”
• Upper bracket “2”
TIP
• Temporarily tighten the pinch bolts (lower
bracket).
• Do not tighten the pinch bolts (upper bracket)
yet. Steering ring nut
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
LS
1 a
LSLS
T R..

STEERING HEAD
4-54
8. Install:
• Steering stem nut “1”
TIP
Apply the lithium-soap-based grease to the
contact surface of the steering stem nut when
installing.
9. After tightening the nut, check the steering
for smooth movement. If not, adjust the
steering by loosening the steering ring nut
little by little.
10.Adjust:
• Front fork top end “a”11.Tighten:
• Pinch bolt (upper bracket) “1”
• Pinch bolt (lower bracket) “2”
EWA33DD049
WARNING
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction. Steering stem nut
145 Nm (14.5 m·kgf, 105 ft·lbf)
Front fork top end (standard) “a”
0 mm (0 in)T R..
a
Upper bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
Lower bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
T R..
T R..
21

REAR SHOCK ABSORBER ASSEMBLY
4-55
EASB111174
REAR SHOCK ABSORBER ASSEMBLY
Removing the rear shock absorber assembly
Order Part name Q’ty Remarks
Seat Refer to “GENERAL CHASSIS” on page 4-1.
Side cover (left / right) Refer to “GENERAL CHASSIS” on page 4-1.
Air scoop (left / right) Refer to “GENERAL CHASSIS” on page 4-1.
Fuel tank Refer to “FUEL TANK” on page 7-1.
1 Rear shock absorber assembly lower bolt 1
2 Rear shock absorber assembly upper bolt 1
3 Rear shock absorber assembly 1
4 Locknut 1
5 Adjusting nut 1
6 Lower spring guide 1
7 Upper spring guide 1
8Spring 1
9 Dust seal 2
2
12
1615
1413
12
14
4
5
7
6
83
9
9 10
10 11
1
New
New
13New
LS
LS
M
M
M
M
M

REAR SHOCK ABSORBER ASSEMBLY
4-56
10 Collars 2
11 Bushing 1
12 Collars 2
13 O-ring 2
14 Dust seal 2
15 Stopper ring 1
16 Bearing 1
For installation, reverse the removal proce-
dure.
Removing the rear shock absorber assembly
Order Part name Q’ty Remarks
2
12
1615
1413
12
14
4
5
7
6
83
9
9 10
10 11
1
New
New
13New
LS
LS
M
M
M
M
M