warning YAMAHA YFZ450R 2021 Workshop Manual

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.
UBKD60E0.book Page 43 Wednesday, November 18, 2020 8:39 AM

9-46
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
UBKD60E0.book Page 46 Wednesday, November 18, 2020 8:39 AM

9-51
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

9-53
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.
UBKD60E0.book Page 53 Wednesday, November 18, 2020 8:39 AM

10-1
10
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
UBKD60E0.book Page 1 Wednesday, November 18, 2020 8:39 AM

11-4
11
Spring:Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
250 mm (9.9 in)Rear suspension:Type:Swingarm (link suspension)
Spring:
Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel: 280 mm (11.0 in)Electrical system:System voltage:12 V
Ignition system: TCI
Charging system:
AC magnetoBattery:Model:YTZ7S
Voltage, capacity:
12 V, 6.0 AhLights:Headlight:T19L, 30.0 W/30.0 W Brake/tail light:
LED
Neutral indicator light: LED
Fuel level warning light:
LED
Coolant temperature warning light: LED
Engine trouble warning light: LED
Fuses:Main fuse:20.0 AEBU30403Noise and vibration levels statement (for Eu-
rope)
The figures quoted are emission levels and are not
necessarily safe working levels. Whilst there is a
correlation between the emission and exposure
levels, this cannot be used reliably to determine
whether or not further precautions are required.
Factors that influence the actual level of exposure
of work-force include the characteristics of the
work room, the other sources of noise, etc. i.e. the
number of machines and other adjacent process-
es, and the length of time for which an operator is
exposed to the noise. Also the permissible expo-
UBKD60E0.book Page 4 Wednesday, November 18, 2020 8:39 AM

12-1
12
INDEX
AAccessories and loading ................................................ 7-5
Air filter element, cleaning ........................................... 9-22BBattery ......................................................................... 9-43
Brake and clutch levers, checking and lubricating ...... 9-39
Brake fluid, changing ................................................... 9-31
Brake fluid level, checking ........................................... 9-30
Brake lever ..................................................................... 5-5
Brake lever free play, checking the front ..................... 9-32
Brake light switches ..................................................... 9-34
Brake pads, checking the front and rear ..................... 9-29
Brake pedal .................................................................... 5-6
Brake pedal, checking and lubricating ........................ 9-40
Brake pedal height, checking ...................................... 9-32
Brakes .......................................................................... 9-28
Brakes, front and rear .................................................... 6-4
Brake/tail light .............................................................. 9-49CCables, checking and lubricating ................................ 9-38
Chassis fasteners .......................................................... 6-7
Cleaning ....................................................................... 10-1
Clutch lever .................................................................... 5-5
Clutch lever free play, adjusting .................................. 9-35
Coolant .................................................................6-4, 9-20
Coolant, changing ........................................................ 9-22
Coolant temperature warning light ................................ 5-2
Cowling and panels, removing and installing .............. 9-10
DDrive chain ..................................................................... 6-5
Drive chain, lubricating ................................................ 9-38
Drive chain slack .......................................................... 9-36EEngine break-in .............................................................. 7-4
Engine oil ....................................................................... 6-4
Engine oil and oil filter element .................................... 9-14
Engine, start ................................................................... 7-1
Engine stop switch ........................................................ 5-3
Engine trouble warning light .......................................... 5-2FFuel ......................................................................... 5-9, 6-4
Fuel level warning light .................................................. 5-2
Fuel tank cap ................................................................. 5-8
Fuse, replacing ............................................................ 9-46HHandlebar position, adjusting ...................................... 5-23
Handlebar switches ....................................................... 5-3
Headlight beam, adjusting ........................................... 9-49
Headlight bulb, replacing ............................................. 9-46IIdentification numbers ................................................... 1-1
Indicator light and warning lights ................................... 5-1
Instruments, lights and switches ................................... 6-7LLabel locations ............................................................... 2-1
Light switch ................................................................... 5-3
UBKD60E0.book Page 1 Wednesday, November 18, 2020 8:39 AM

EBU26174
WARNING
ALWAYS
:
• use proper riding techniques to avoid
vehicle overturns on hills and rough
terrain and in turns.

seriously affect handling and control.
Improper ATV use can result in SEVERE INJURY or DEATH.
NEVER USE
WITH DRUGS
OR ALCOHOL
ALWAYS USE
AN APPROVED HELMET AND
PROTECTIVE GEAR NEVER USE
ON PAVED ROADS NEVER CARRY
PASSENGERS
NEVER
operate:


conditions.

another vehicle.

balance and steering and increase risk
of losing control.
LOCATE AND READ OWNER’S MANUAL. FOLLOW ALL INSTRUCTIONS AND WARNINGS.\
PRINTED IN USA
2020.11-0.3× 1 CR (E)
UBKD60E0.book Page 1 Wednesday, November 18, 2020 8:39 AM