YAMAHA YFZ450R 2021 Owners Manual

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9
EBU29963Replacing the fuseThe fuse holder is located under the seat. (See
page 5-10.)
If the fuse is blown, replace it as follows.1. Turn the key to “ ” (off) and turn off all elec- trical circuits.NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse.
2. Remove the blown fuse, and then install anew fuse of the specified amperage.
WARNING! Always use a fuse of the spec- ified rating, and never use a substitute ob-
ject in place of the proper fuse. An
improper fuse or a substitute object can
cause damage to the electrical system,
which could lead to a fire.
[EWB02173]
3. Turn the key to “ ” (on) and turn on the elec- trical circuits to check if the devices operate.
4. If the fuse immediately blows again, have a Yamaha dealer check the electrical system.EBU30873Replacing a headlight bulbIf a headlight bulb burns out, replace it with the
specified bulb as follows.1. Remove the headlight unit by removing the bolt and pulling the headlight unit outward as
shown.
1. Fuse
2. Spare fuse
1
2
Specified fuse:20.0 A
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92. Remove the bulb cover. 3. Remove the socket by pushing it in and turn-
ing it counterclockwise, and then remove the
burnt-out bulb.
4. Place a new headlight bulb into position. NOTICE: Do not touch the glass part of the
bulb. Oil from your fingers or other con-
tamination will adversely affect the trans-
parency of the glass, luminosity of the
bulb, and bulb life. Thoroughly clean off
any dirt and fingerprints using a cloth
moistened with alcohol or thinner.
[ECB00653]
1. Headlight unit
2. Bolt
1. Bulb cover
1
2
1
1. Socket
1
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9
5. Install the socket by pushing it in and turning
it clockwise.
6. Install the bulb cover.
TIPWhen installing the bulb cover, make sure the
“TOP” mark faces upwards.
7. Place the headlight unit in the original posi- tion, and then install the bolt.
1. Do not touch the glass part of the bulb.
1. Bulb cover
2. “TOP” mark
12
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98. Adjust the headlight beam if necessary.
EBU25562Adjusting a headlight beamNOTICEECB00691It is advisable to have a Yamaha dealer make
this adjustment. To raise a headlight beam, turn the headlight
beam adjusting bolt in direction (a).
To lower a headlight beam, turn the adjusting bolt
in direction (b).
EBU26922Brake/tail lightThis model is equipped with an LED type of
brake/tail light.
If the brake/tail light does not come on, have a
Yamaha dealer check it.EBU25653Removing a wheel1. Park the ATV on a level surface.
2. Loosen the wheel nuts.
3. Elevate the ATV and place a suitable stand under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
1. Headlight beam adjusting bolt
1
(a)
(b)
1. Wheel nut
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EBU27484Installing a wheel1. Install the wheel with the arrow mark pointingin the forward rotating direction of the wheel,
and then install the wheel nuts.
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified torques.
EBU25741TroubleshootingAlthough Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the
fuel, compression, or ignition systems, for exam-
ple, can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vi-
tal systems yourself. However, should your ATV
require any repair, take it to a Yamaha dealer,
whose skilled technicians have the necessary
tools, experience, and know-how to service the
ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
1. Arrow mark
2. Forward rotating direction
3. Wheel nut
2
3
3
Tightening torques: Front wheel nut:45 N·m (4.5 kgf·m, 33 lb·ft)
Rear wheel nut: 45 N·m (4.5 kgf·m, 33 lb·ft)
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9
WARNING
EWB02281Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces. UBKD60E0.book Page 51 Wednesday, November 18, 2020 8:39 AM

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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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9Engine overheating
WARNING
EWB02291Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIP
Tap water can be used in an emergency. Change to the recommended coolant as soon as possible.
 The engine will tend to overheat if the radiator is caked with mud, or if the ATV is overloaded. Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
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EBU25861
CLEANING AND STORAGE
EBU25903CleaningFrequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply
degreaser to the chain, sprockets or wheel
axles.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the
job. WARNING! Wet brakes may have re-
duced stopping ability, increasing the
chance of an accident. Test the brakes af-
ter washing. Apply the brakes several
times at slow speeds to let friction dry out
the linings.
[EWB02312]
NOTICE: Excessive wa- ter pressure may cause water seepage
and deterioration of wheel bearings,
brakes, transmission seals and electrical
devices. Many expensive repair bills have
resulted from improper high-pressure de-
tergent applications such as those avail-
able in coin-operated car washers.
[ECB00712]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or
bottle brush is handy for hard-to-reach plac-
es.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Dry the chain and lubricate it to prevent it from rusting.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
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10abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
EBU27264StorageShort-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.
NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00722]
Long-term
Before storing your ATV for several months: 1. Make any necessary repairs and perform all outstanding maintenance.
2. Follow all the instructions in the Cleaning sec- tion of this chapter. 3. Fill up the fuel tank and add fuel stabilizer (Fu-
el Med Rx if available), and then run the en-
gine for 5 minutes to distribute the treated
fuel.
4. Perform the following steps to protect the en- gine from internal corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall
with oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
5. Lubricate all control cables and the pivoting points of all levers and pedals.
Specified amount:
7.5 ml per liter of fuel (1 oz per gallon)UBKD60E0.book Page 2 Wednesday, November 18, 2020 8:39 AM