battery YAMAHA YFZ450R 2021 Owners Manual

Lubricating the upper and lower arm pivots ...................................................... 9-41
Lubricating the steering shaft ................... 9-42
Battery....................................................... 9-43
Replacing the fuse .................................... 9-46
Replacing a headlight bulb ....................... 9-46
Adjusting a headlight beam ...................... 9-49
Brake/tail light ........................................... 9-49
Removing a wheel ..................................... 9-49
Installing a wheel....................................... 9-50
Troubleshooting ........................................ 9-50
Troubleshooting charts ............................. 9-52
CLEANING AND STORAGE ......................... 10-1 Cleaning .................................................... 10-1
Storage...................................................... 10-2
SPECIFICATIONS ........................................ 11-1
INDEX ........................................................... 12-1
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3-5
3
4. Once immediate safety hazards are con-
firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
Aftermarket Parts, Accessories, and Modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of po-
tential safety hazards to you or others. Installing
aftermarket products or having other modifica-
tions performed to your vehicle that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious
injury or death. You are responsible for injuries re-
lated to changes in the vehicle. Keep the following guidelines in mind, as well as those found in the
Loading section (page 7-6) when mounting acces-
sories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
gerous loss of lights or engine power. Also, the
battery tends to discharge more quickly if elec-
trical accessories are added.
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4-1
4
EBU17681
DESCRIPTION
EBU17691Left view
EBU17701Right view
1. Front shock absorber
2. Engine oil tank filler cap
3. Rear brake fluid reservoir
4. Battery
5. Shift pedal
6. Coolant reservoir
563
1
4
2
1. Spark arrester
2. Fuse
3. Fuel tank cap
4. Oil filter element
5. Brake pedal
6. Rear brake light switch
7. Rear shock absorber
456
2
1
7
3
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5
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). The
warning light should come on for a few seconds,
and then go off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.
EBU18068Handlebar switches
EBU18081Engine stop switch “ / ”
Set this switch to “ ” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this
switch to stop the engine in an emergency situa-
tion. The engine will not start or run when this
switch is set to “ ”.EBU18102Start switch “ ”
Push this switch to crank the engine with the start-
er. See the starting instructions on page 7-1 prior
to starting the engine.EBU18157Light switch “ / /OFF”
Set this switch to “ ” to turn on the low beams
and the taillight. Set the switch to “ ” to turn on
the high beams and the taillight. Set the switch to
“OFF” to turn off all the lights.NOTICEECB00046Do not use the headlights with the engine
turned off for an extended period of time. The
battery may discharge to the point that the
1. Light switch “ / /OFF”
2. Engine stop switch “ / ”
3. Start switch “ ”
1
23
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7-2
7
TIPIf 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 attempt. NOTICEECB00164For maximum engine life, never accelerate
hard when the engine is cold! EBU20525ShiftingThis ATV has a 5-speed forward transmission. The
transmission allows you to control the amount of
power you have available at a given speed or for
starting, accelerating, climbing hills, etc.
To shift into neutral, release the throttle lever, ap-
ply the clutch, and then repeatedly depress the
shift pedal until it stops.
When it stops, it will be in first gear. Raise the ped-
al slightly to reach the neutral position, and then
release the clutch.
EBU20595To start out and accelerate1. Release the throttle lever, apply the front or rear brake, and then release the parking
brake.
2. Pull the clutch lever to disengage the clutch.
3. Shift into first gear, and then release the brake. NOTICE: Always close the throttle
before shifting gears, otherwise damage
to the engine and drive train may result.
[ECB01220]
1. Shift pedal
2. Neutral position
1
1
N
2 3
4
5
2
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9-43
9
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU2918BBatteryThis model is equipped with a 12-volt VRLA
(valve-regulated lead-acid) battery. There is no
need to check the electrolyte or to add distilled
water. However, the battery lead connections
need to be checked and tightened, and the bat-
tery terminals cleaned if corroded. If the battery
seems to have discharged, recharge it as soon as
possible.TIPWear gloves and eye protection in a ventilated
area away from sparks and open flames. Wash
hands after handling.
 It is recommended to have the battery serviced
by a Yamaha dealer.
WARNING
EWB02161Battery 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
ignition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN. To remove the battery
1. Remove the seat. (See page 5-10.)
2. Remove the battery holding plate by remov- ing the bolts.
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9
3. Disconnect the negative battery lead first,
then the positive battery lead by removing
their bolt. NOTICE: When removing the bat-
tery, the main switch must be off, and the
negative lead must be disconnected be-
fore the positive lead.
[ECB01002]
4. Pull the battery out of its compartment.
NOTICEECB00622Never attempt to open the battery or remove
the battery cell seals, as this would permanent-
ly damage the battery. To charge the battery
 Confirm the recommended charging rate as
specified on the battery itself.
 Select a suitable charger and follow the manu-
facturer’s instructions.NOTICEECB00933To charge a VRLA (valve-regulated lead-acid)
battery, a special battery charger is required.
Using a conventional battery charger will dam-
age the battery. To store the battery
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.
 If the battery will be stored for more than two
months, check it at least once a month and fully
charge it if necessary.
1. Bolt
2. Battery holding plate
3. Negative battery lead (black)
4. Positive battery lead (red)
1
1
2
3
4
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9-45
9
NOTICEECB00942Always keep the battery charged. Storing the
battery in a discharged state for an extended
period of time will cause permanent battery
damage.
 Do not store the battery in an excessively
cold or warm place [below freezing or above
30 °C (90 °F)]. To install the battery
1. Place the battery in its compartment.
2. Connect the positive battery lead first, then connect the negative battery lead by installing
their bolt. NOTICE: When installing the bat-
tery, the main switch must be off, and the
positive lead must be connected before
the negative lead.
[ECB01111]
3. Install the battery holding plate by installing the bolts.
4. Install the seat. (See page 5-10.)TIP Make sure the positive and negative battery
leads are installed as shown.
 Fully charge the battery before installing it. 1. Positive battery lead (red)
2. Negative battery lead (black)
2
1
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9
EBU27696Troubleshooting chartsStarting 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 battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
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.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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10-3
10
6. Put the frame on stands or blocks to raise all
wheels off the ground. (Alternatively, turn the
wheels each month to prevent the tires from
degrading in one spot.)
7. Cover the muffler outlet with a plastic bag to prevent moisture from entering it.
8. Remove the battery and fully charge it. (See page 9-43.)
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