2008 YAMAHA YFZ450 battery

Parking ...................................................... 6-5
Parking on a slope .................................... 6-6
Accessories and loading ........................... 6-6
RIDING YOUR ATV ...................................... 7-1
GETTING TO KNOW YOUR ATV.............. 7-2
RIDE WITH CARE AND GOOD
JUDGEMENT ........................................... 7-2
BE CAREFUL WHERE YOU RIDE ............ 7-8
TURNING YOUR ATV ............................. 7-12
CLIMBING UPHILL .................................. 7-14
RIDING DOWNHILL................................. 7-16
CROSSING A SLOPE.............................. 7-17
CROSSING THROUGH SHALLOW
WATER .................................................. 7-18
RIDING OVER ROUGH TERRAIN .......... 7-20
SLIDING AND SKIDDING ........................ 7-20
WHAT TO DO IF... ................................... 7-21
WHAT TO DO... ....................................... 7-21
PERIODIC MAINTENANCE AND MINOR
REPAIR .......................................................... 8-1
Owner’s manual and tool kit ...................... 8-1
Periodic maintenance chart for the
emission control system .......................... 8-3
General maintenance and lubrication
chart ........................................................ 8-5
Removing and installing the panel ............ 8-9
Checking the spark plug .......................... 8-10Engine oil and oil filter element ................ 8-14
Coolant .................................................... 8-20
Cleaning the air filter element .................. 8-24
Cleaning the spark arrester ..................... 8-28
Adjusting the carburetor ........................... 8-29
Checking the engine idling speed ............ 8-30
Adjusting the throttle cable free play ........ 8-30
Valve clearance ....................................... 8-31
Checking the front and rear brake pads .. 8-31
Checking the brake fluid level .................. 8-32
Changing the brake fluid .......................... 8-35
Checking the front brake lever free
play ........................................................ 8-36
Checking the brake pedal position ........... 8-36
Adjusting the parking brake free play ...... 8-37
Brake light switches ................................. 8-39
Adjusting the clutch lever free play .......... 8-39
Lubricating the drive chain ....................... 8-41
Checking and lubricating the cables ........ 8-41
Checking and lubricating the brake and
clutch levers ........................................... 8-42
Checking and lubricating the brake and
shift pedals............................................. 8-43
Checking the wheel hub bearings ............ 8-43
Lubricating the swingarm pivots .............. 8-43
Lubricating the upper and lower arm
pivots ..................................................... 8-44
Battery ..................................................... 8-45
Replacing the fuse ................................... 8-46

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Position (1):

Cold engine start with ambient temperature be-
low 5 °C (40 °F).
Position (2):

Cold engine start with ambient temperature be-
tween 0 °C (30 °F) and 30 °C (90 °F).
Position (3):

Cold engine start with ambient temperature
above 25 °C (80 °F).
Ambient temp./starter (choke) position
6. Completely close the throttle lever and start
the engine by pushing the start switch.
NOTE:

If the engine fails to start, release the start switch,
then push it again. Pause a few seconds before
the next attempt. Each cranking should be as short
as possible to preserve battery energy. Do not
crank the engine more than 10 seconds on each
1. Fully open
2. Half open
3. Closed
4. Starter (choke)
1
23
123
4

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Right side

EBU25222
Battery
This model is equipped with a sealed-type (MF)
battery, which does not require any maintenance.
There is no need to check the electrolyte or to add
distilled water. Check and, if necessary, tighten the
battery lead connections.
CAUTION:

ECB00620
Never attempt to remove the battery cell seals,
as this would permanently damage the battery.WARNING
EWB02160
Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause severe burns. Avoid contact with skin,
eyes or clothing. Always shield your eyes
when working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of ig-
nition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN.
To charge the battery
Have a Yamaha dealer charge the battery as soon
as possible if it seems to have discharged. Keep in
mind that the battery tends to discharge more
quickly if the ATV is equipped with optional electri-
cal accessories.
1. Upper grease nipple
2. Lower grease nipple
2 1

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To store the battery
1. If the ATV will not be used for more than one
month, remove the battery, fully charge it, and
then place it in a cool, dry place.
2. If the battery will be stored for more than two
months, check it at least once a month and ful-
ly charge it if necessary.
To install the battery
NOTE:

Be sure the battery is fully charged.
1. Place the battery in its compartment.
2. Make sure to properly connect the battery
leads to the battery terminals.
CAUTION:

ECB00630

Always keep the battery charged. Storing a
discharged battery can cause permanent
battery damage.

To charge a sealed-type (MF) battery, a spe-
cial constant-voltage battery charger is re-
quired. Using a conventional battery charger
will damage the battery. If you do not have
access to a constant-voltage battery charg-
er, have a Yamaha dealer charge your bat-
tery.
EBU25262
Replacing the fuse
The fuse holder is located on the right side of the
ATV.
If the fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off all electrical
circuits.
CAUTION:

ECB00640
To prevent accidental short-circuiting, turn off
1. Fuse
2. Spare fuse
1
2

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EBU25781
Troubleshooting charts
Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the ATV.
The engine does not start.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.

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with oil.)
e. Remove the spark plug cap from the spark
plug, and then install the spark plug and
the spark plug cap.
6. Lubricate all control cables and the pivoting
points of all levers and pedals.
7. Check and, if necessary, correct the tire air
pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
ly, turn the wheels a little every month in order
to prevent the tires from becoming degraded
in one spot.
8. Cover the muffler outlet with a plastic bag to
prevent moisture from entering it.
9. Remove the battery and fully charge it. Store
it in a cool, dry place and charge it once a
month. Do not store the battery in an exces-
sively cold or warm place [less than 0 °C (30
°F) or more than 30 °C (90 °F)]. For more in-
formation on storing the battery, see page
8-45.
NOTE:

Make any necessary repairs before storing the
ATV.

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Rear brake:

Type:
Single disc brake
Operation:
Right foot operation
Recommended fluid:
DOT 4
Front suspension:
Type:
Double wishbone
Spring/shock absorber type:
Coil spring/gas-oil damper
Wheel travel:
230 mm (9.1 in)
Rear suspension:
Type:
Swingarm (link suspension)
Spring/shock absorber type:
Coil spring/gas-oil damper
Wheel travel:
270 mm (10.6 in)
Electrical system:
Ignition system:
DC. CDI
Charging system:
AC magneto
Battery:
Model:
GT7B-4
Voltage, capacity:
12 V, 6.5 Ah
Headlight:
Bulb type:
Krypton bulb
Bulb voltage, wattage x quantity:
Headlight:
12 V, 30.0/30.0 W
×
2
Tail/brake light:
12 V, 0.5/3.9 W
×
1
Neutral indicator light:
12 V, 1.7 W
×
1
Coolant temperature warning light:
12 V, 1.7 W
×
1

Fuses:
Main fuse:
15.0 A

INDEX
A
Accessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-24
B
Battery .......................................................................... 8-45
Brake and clutch levers, checking and lubricating ....... 8-42
Brake and shift pedals, checking and lubricating ......... 8-43
Brake fluid, changing.................................................... 8-35
Brake fluid level, checking............................................ 8-32
Brake lever ..................................................................... 4-5
Brake lever free play, checking the front ...................... 8-36
Brake light switches ..................................................... 8-39
Brake pads, checking the front and rear ...................... 8-31
Brake pedal .................................................................... 4-5
Brake pedal position, checking .................................... 8-36
Brakes, front and rear .................................................... 5-4
C
Cables, checking and lubricating ................................. 8-41
Carburetor, adjusting.................................................... 8-29
Chassis fasteners........................................................... 5-8
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-5
Clutch lever free play, adjusting ................................... 8-39
Coolant ................................................................. 5-4
,
8-20
Coolant temperature warning light ................................. 4-1
D
Drive chain ..................................................................... 5-5
Drive chain, lubricating ................................................. 8-41
E
Engine break-in .............................................................. 6-5
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-30
Engine oil ....................................................................... 5-4
Engine oil and oil filter element .................................... 8-14
Engine, starting a warm ................................................. 6-3
Engine stop switch ......................................................... 4-2
F
Fuel ........................................................................ 4-8
,
5-4
Fuel cock ........................................................................ 4-9
Fuel tank cap.................................................................. 4-7
Fuse, replacing............................................................. 8-46
H
Handlebar switches ........................................................ 4-2
Headlight beam, adjusting............................................ 8-49
Headlight bulb, replacing.............................................. 8-47
I
Identification numbers .................................................. 11-1
Indicator light and warning light...................................... 4-1
Instruments, lights and switches .................................... 5-8
K
Key identification number ............................................. 11-1