2007 YAMAHA YZ450F warning

5 - 24
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
Brake hose holder 1
Screw (brake hose holder) 2
CAUTION:
After installing the brake hose holders,
make sure the brake hose does not contact
the spring (rear shock absorber). If it does,
correct its twist.
Brake fluid
1. Fill:
Brake fluid
Until the fluid level reaches “LOWER”
level line a.
WARNING
Use only the designated quality brake
fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
Refill with the same type of brake fluid;
mixing fluids may result in a harmful
chemical reaction and lead to poor perfor-
mance.
Be careful that water does not enter the
master cylinder when refilling. Water will
significantly lower the boiling point of the
fluid and may result in vapor lock.
CAUTION:
Brake fluid may erode painted surfaces or
plastic parts. Always clean up spilled fluid
immediately.
ÈFront
ÉRear
Recommended brake fluid:
DOT #4
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
È
É

5 - 26
CHASFRONT FORK
EC550000
FRONT FORK
Extent of removal:
1 Front fork removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT FORK REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is no
danger of it falling over.
Front wheel Refer to “FRONT WHEEL AND REAR
WHEEL” section.
Front caliper Refer to “FRONT BRAKE AND REAR
BRAKE” section.
Number plate Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
1 Protector 1
2 Pinch bolt (handle crown) 2 Only loosening.
3 Damper assembly 1 Loosen when disassembling the front
fork.
Use special tool.
Refer to “REMOVAL POINTS”.
4 Pinch bolt (under bracket) 2 Only loosening.
5 Front fork 1
1

5 - 32
CHASFRONT FORK
EC554502
Inner tube
1. Inspect:
Inner tube surface a
Score marks → Repair or replace.
Use #1,000 grit wet sandpaper.
Damaged oil lock piece → Replace.
Inner tube bends
Out of specification → Replace.
Use the dial gauge 1.
NOTE:
The bending value is shown by one half of the
dial gauge reading.
WARNING
Do not attempt to straighten a bent inner
tube as this may dangerously weaken the
tube.
Inner tube bending limit:
0.2 mm (0.008 in)
EC554600
Outer tube
1. Inspect:
Outer tube 1
Score marks/wear/damage → Replace.
Adjuster
1. Inspect:
Adjuster 1
O-ring 2
Wear/damage → Replace.

5 - 40
CHAS
30. Install:
Adjuster 1
To inner tube.
T R..55 Nm (5.5 m · kg, 40 ft · lb)
31. Fill:
Front fork oil 1
From outer tube top.
* For EUROPE
WARNING
Never fail to make the oil amount adjust-
ment between the maximum and minimum
amount and always adjust each front fork
to the same setting. Uneven adjustment
can cause poor handling and loss of stabil-
ity.
CAUTION:
Be sure to use recommended fork oil. If
other oils are used, they may have an
excessively adverse effect on the front
fork performance.
Never allow foreign materials to enter the
front fork.
Recommended oil:
Suspension oil “S1”
Standard oil amount:
340 cm
3 (12.0 Imp oz, 11.5 US oz)
*350 cm3 (12.3 Imp oz, 11.8 US oz)
Extent of adjustment:
300 ~ 380 cm
3
(10.6 ~ 13.4 Imp oz,
10.1 ~ 12.8 US oz)
32. Install:
Damper assembly 1
To outer tube.
NOTE:
Temporarily tighten the damper assembly.
FRONT FORK

5 - 44
CHAS
EC5B3000
REMOVAL POINTS
EC5B3100
Master cylinder
1. Remove:
Master cylinder bracket 1
Master cylinder 2
CAUTION:
Do not let the master cylinder hang on the
brake hose.
Keep the master cylinder cap side hori-
zontal to prevent air from coming in.
EC5B3200
Grip
1. Remove:
Grip 1
NOTE:
Blow in air between the handlebar or tube
guide and the grip. Then remove the grip
which has become loose.
EC5B4000
INSPECTION
EC5B4100
Handlebar
1. Inspect:
Handlebar 1
Bends/cracks/damage → Replace.
WARNING
Do not attempt to straighten a bent handle-
bar as this may dangerously weaken the
handlebar.
EC5B5000
ASSEMBLY AND INSTALLATION
Handlebar
1. Install:
Handlebar holder (lower) 1
Plain washer 2
Nut [handlebar holder (lower)] 3
NOTE:
Install the handlebar holder (lower) with its
side having the greater distance a from the
mounting bolt center facing forward.
Apply the lithium soap base grease on the
thread of the handlebar holder (lower).
Installing the handlebar holder (lower) in the
reverse direction allows the front-to-rear off-
set amount of the handlebar position to be
changed.
Do not tighten the nut yet.
HANDLEBAR

5 - 47
CHASHANDLEBAR
8. Install:
•Throttle cable cap 1
•Screw (throttle cable cap) 2
WARNING
After tightening the screws, check that the
throttle grip
3 moves smoothly. If it does
not, retighten the bolts for adjustment.
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)
9. Install:
•Cover (grip cap) 1
•Cover (throttle cable cap) 2
10. Install:
•Master cylinder 1
•Master cylinder bracket 2
•Bolt (master cylinder bracket) 3
NOTE:
•Install the bracket so that the arrow mark a
faces upward.
•First tighten the bolt on the upper side of the
master cylinder bracket, and then tighten the
bolt on the lower side.
T R..9 Nm (0.9 m · kg, 6.5 ft · lb)

5 - 49
CHAS
EC560000
STEERING
Extent of removal:
1 Under bracket removal
2 Bearing removal
Extent of removal Order Part name Q’ty Remarks
STEERING REMOVAL
WARNING
Support the machine securely so there is no
danger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Number plate Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
Handlebar Refer to “HANDLEBAR” section.
Front fender
1 Steering shaft nut 1
2 Front fork 2 Refer to “FRONT FORK” section.
3 Handle crown 1
4 Ring nut 1 Use special tool.
Refer to “REMOVAL POINTS”.
5 Under bracket 1
6 Bearing race cover 1
7 Bearing (upper) 1
8 Bearing (lower) 1
Refer to “REMOVAL POINTS”.
9 Bearing race 2
2
1
STEERING

5 - 50
CHAS
EC563000
REMOVAL POINTS
EC563202
Ring nut
1. Remove:
•Ring nut 1
Use the ring nut wrench 2.
WARNING
Support the steering shaft so that it may
not fall down.
Ring nut wrench:
YU-33975/90890-01403
EC563300
Bearing (lower)
1. Remove:
•Bearing (lower) 1
Use the floor chisel 2.
CAUTION:
Take care not to damage the steering shaft
thread.
Bearing race
1. Remove:
•Bearing race 1
Remove the bearing race using long rod
2 and the hammer.
EC564000
INSPECTION
EC564200
Steering shaft
1. Inspect:
•Steering shaft 1
Bend/damage → Replace.
STEERING