warning YAMAHA WR 450F 2003 User Guide

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INSP
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CHASSIS/BRAKE SYSTEM AIR BLEEDING
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
WARNING
Bleed the brake system if:
The system has been disassembled.
A brake hose has been loosened or
removed.
The brake fluid is very low.
The brake operation is faulty.
A dangerous loss of braking performance
may occur if the brake system is not prop-
erly bled.
1. Remove:
Master cylinder cap
Diaphragm
Protector (rear brake)
2. Bleed:
Brake fluid
ÅFront
ıRear
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube 2 tightly
to the caliper bleed screw 1.
d. Place the other end of the tube into a
container.
e. Slowly apply the brake lever or pedal
several times.
f. Pull the lever in or push down on the
pedal. Hold the lever or pedal in position.
g. Loosen the bleed screw and allow the
lever or pedal to travel towards its limit.
h. Tighten the bleed screw when the lever
or pedal limit has been reached; then
release the lever or pedal.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
Å
ı

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INSP
ADJ
FRONT BRAKE ADJUSTMENT
3. Install:
Protector (rear brake)
Diaphragm
Master cylinder cap
NOTE:
If bleeding is difficult, it may be necessary to
let the brake fluid system stabilize for a few
hours. Repeat the bleeding procedure when
the tiny bubbles in the system have disap-
peared.
j. Add brake fluid to the level line on the
reservoir.
WARNING
Check the operation of the brake after
bleeding the brake system.
EC362040
FRONT BRAKE ADJUSTMENT
1. Check:
Brake lever position a
Brake lever position a:
Standard position Extent of adjustment
95 mm (3.74 in)76 ~ 97 mm
(2.99 ~ 3.82 in)
2. Remove:
Lever cover
3. Adjust:
Brake lever position
4. Install:
Lever cover Brake lever position adjustment steps:
Loosen the locknut 1.
Turn the adjusting bolt 2 until the lever
position a is within specified position.
Tighten the locknut.
T R..
Locknut:
5 Nm (0.5 m • kg, 3.6 ft • lb)
CAUTION:
Be sure to tighten the locknut, as it will
cause poor brake performance.

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INSP
ADJREAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
EC364002
REAR BRAKE ADJUSTMENT
1. Check:
Brake pedal height a
Out of specification → Adjust.
Brake pedal height a:
5 mm (0.20 in)
2. Adjust:
Brake pedal height
Pedal height adjustment steps:
Loosen the locknut 1.
Turn the adjusting nut 2 until the pedal
height a is within specified height.
Tighten the locknut.
WARNING
Adjust the pedal height between the
maximum Å and the minimum ı as
shown. (In this adjustment, the bolt 3
end b should protrude out of the
threaded portion 4 but not be less
than 2 mm (0.08 in) c away from the
brake pedal 5).
After the pedal height adjustment, make
sure that the rear brake does not drag.
Å
ı
EC365080
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
Brake pad thickness a
Out of specification → Replace as a
set.
2. Replace:
Brake pad
Brake pad thickness a:
Standard
4.4 mm (0.17 in) 1.0 mm (0.04 in)
Brake pad replacement steps:
Remove the pad pin plug 1.

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INSP
ADJ

REAR BRAKE PAD INSULATOR INSPECTION/
BRAKE FLUID LEVEL INSPECTION
3. Inspect:

Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:

Brake pedal operation
A softy or spongy feeling
→
Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
EC36b000
REAR BRAKE PAD INSULATOR
INSPECTION
1. Remove:

Brake pad
Refer to “REAR BRAKE PAD INSPEC-
TION AND REPLACEMENT” section.
2. Inspect:

Rear brake pad insulator
1

Damage
→
Replace.
EC367001
BRAKE FLUID LEVEL INSPECTION
1. Place the master cylinder so that its top is
in a horizontal position.
2. Inspect:

Brake fluid level
Fluid at lower level
→
Fill up.
a
Lower level
Å
Front
ı
Rear
WARNING


Use only designated quality brake fluid to
avoid poor brake performance.

Refill with same type and brand of brake
fluid; mixing fluids could result in poor
brake performance.

Be sure that water or other contaminants
do not enter master cylinder when refill-
ing.

Clean up spilled fluid immediately to
avoid erosion of painted surfaces or plas-
tic parts.
Recommended brake fluid:
DOT #4
Å
ı

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INSP
ADJFRONT FORK COMPRESSION DAMPING FORCE
ADJUSTMENT
STANDARD POSITION:
This is the position which is back by the spe-
cific number of clicks from the fully turned-in
position.
* For EUROPE, AUS, NZ and ZA
CAUTION:
Do not force the adjuster past the minimum
or maximum extent of adjustment. The
adjuster may be damaged.
WARNING
Always adjust each front fork to the same
setting. Uneven adjustment can cause poor
handling and loss of stability.
Standard position:
10 clicks out
* 8 clicks out
EC36J001
FRONT FORK COMPRESSION DAMPING
FORCE ADJUSTMENT
1. Remove:
Rubber cap
2. Adjust:
Compression damping force
By turning the adjuster 1.
Stiffer a →Increase the compression
damping force. (Turn the
adjuster 1 in.)
Softer b →Decrease the compression
damping force. (Turn the
adjuster 1 out.)
Extent of adjustment:
Maximum Minimum
Fully turned in
position20 clicks out
(from maximum
position)

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INSP
ADJ
REAR SHOCK ABSORBER INSPECTION
STANDARD POSITION:
This is the position which is back by the spe-
cific number of clicks from the fully turned-in
position.
CAUTION:
Do not force the adjuster past the minimum
or maximum extent of adjustment. The
adjuster may be damaged.
WARNING
Always adjust each front fork to the same
setting. Uneven adjustment can cause poor
handling and loss of stability.
3. Install:
Rubber cap
Standard position:
13 clicks out
EC36K000
REAR SHOCK ABSORBER INSPECTION
1. Inspect:
Swingarm smooth action
Abnormal noise/unsmooth action →
Grease the pivoting points or repair the
pivoting points.
Damage/oil leakage → Replace.

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INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Tighten the ring nut 3 using ring nut
wrench 4.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m • kg, 27 ft • lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
7 Nm (0.7 m • kg, 5.1 ft • lb)
Check the steering shaft by turning it lock
to lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
Install the plain washer 5, handle crown
6, plain washer 7, steering shaft nut 8,
steering shaft cap 9, handlebar 0, han-
dlebar holder A and headlight B.
NOTE:
The handlebar holder should be installed
with the punched mark a forward.
Insert the end of the fuel breather hose C
into the hole in the steering shaft cap.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder, and then tighten
the bolts on the rear side.
T R..
Steering shaft nut:
145 Nm (14.5 m • kg, 105 ft • lb)
Handlebar holder:
28 Nm (2.8 m • kg, 20 ft • lb)
Pinch bolt (handle crown):
23 Nm (2.3 m • kg, 17 ft • lb)
Headlight (left and right):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Headlight (lower):
7 Nm (0.7 m • kg, 5.1 ft • lb)

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INSP
ADJ
BATTERY INSPECTION AND CHARGING
WARNING
Batteries generate explosive hydrogen gas
and contain electrolyte which is made of
poisonous and highly caustic sulfuric acid.
Therefore, always follow these preventive
measures:
Wear protective eye gear when handling
or working near batteries.
Charge batteries in a well-ventilated area.
Keep batteries away from fire, sparks or
open flames (e.g., welding equipment,
lighted cigarettes).
DO NOT SMOKE when charging or han-
dling batteries.
KEEP BATTERIES AND ELECTROLYTE
OUT OF REACH OF CHILDREN.
Avoid bodily contact with electrolyte as it
can cause severe burns or permanent eye
injury.
FIRST AID IN CASE OF BODILY CONTACT:
EXTERNAL
Skin — Wash with water.
Eyes — Flush with water for 15 minutes
and get immediate medical attention.
INTERNAL
Drink large quantities of water or milk fol-
lowed with milk of magnesia, beaten egg
or vegetable oil. Get immediate medical
attention.
CAUTION:
Charging time, charging amperage and
charging voltage for an MF battery are dif-
ferent from those of conventional batteries.
The MF battery should be charged as
explained in the charging method illustra-
tions. If the battery is overcharged, the
electrolyte level will drop considerably.
Therefore, take special care when charging
the battery.
BATTERY INSPECTION AND CHARGING

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INSP
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BATTERY INSPECTION AND CHARGING
ÅRelationship between the open-circuit voltage
and the charging time at 20 ˚C (68 ˚F)
(These values vary with the temperature, the
condition of the battery plates, and the electro-
lyte level.)
ıOpen-circuit voltage
ÇCharging time (hours)
ÎTime (minutes)
‰Charging condition of the battery
ÏAmbient temperature 20 ˚C (68 ˚F)
aCharging
bCheck the open-circuit voltage.
5. Charge:
Battery
(refer to the appropriate charging
method illustration)
WARNING
Do not quick charge a battery.
CAUTION:
Never remove the MF battery sealing
caps.
Do not use a high-rate battery charger
since it forces a high-amperage current
into the battery quickly and can cause
battery overheating and battery plate
damage.
If it is impossible to regulate the charging
current on the battery charger, be careful
not to overcharge the battery.
When charging a battery, be sure to
remove it from the machine. (If charging
has to be done with the battery mounted
on the machine, disconnect the negative
battery lead from the battery terminal.)
To reduce the chance of sparks, do not
plug in the battery charger until the bat-
tery charger leads are connected to the
battery.
Check the charge of the battery, as shown
in the charts and the following example.
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20 ~ 30% Å

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INSP
ADJ
REPLACING THE HEADLIGHT BULBS
3. Replace:
Blown fuse
WARNING
Never use a fuse with an amperage rating
other than that specified. Improvising or
using a fuse with the wrong amperage rat-
ing may cause extensive damage to the
electrical system, cause the starting and
ignition systems to malfunction and could
possibly cause a fire.
4. Install:
Fuse cover
Seat Replacement steps:
Set the main switch to “OFF”.
Install a new fuse of the correct amperage.
Set on the switches to verify if the electri-
cal circuit is operational.
If the fuse immediately blows again, check
the electrical circuit.
ItemsAmperage
ratingQ’ty
Main fuse 10 A 1
REPLACING THE HEADLIGHT BULBS
1. Remove:
Headlight
Refer to “SEAT, FUEL TANK AND
SIDE COVERS” section in the CHAP-
TER 4.
2. Remove:
Headlight bulb holder cover 1
3. Detach:
Headlight bulb holder 1
4. Remove:
Headlight bulb 2
WARNING
Since the headlight bulb gets extremely
hot, keep flammable products and your
hands away from the bulb unit it has cooled
down.