2021 YAMAHA YFZ450R warning

5-3
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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
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the adjusting screw in direction (b). Do not
turn the adjusting screw out more than 12
mm (0.47 in) or the throttle cable could be
damaged. Always make sure the throttle lever
free play is adjusted to 2.0–4.0 mm (0.08–
0.16 in). (See page 9-28.)
WARNING! Im-
proper adjustment of the speed limiter and
throttle could cause throttle cable damage
or improper throttle operation. You could
lose control, resulting in an accident.
[EWB00242]
3. Tighten the locknut.EBU18384Clutch lever
The clutch lever is located on the left side of the
handlebar. To disengage the clutch, pull the clutch
lever toward the handlebar grip. To engage the
clutch, release the lever. The lever should be
pulled rapidly and released slowly for smooth
clutch operation.
The clutch lever is equipped with a clutch switch,
which is part of the ignition circuit cut-off system.
(See page 7-1.)EBU18426Brake lever
1. Clutch lever
1. Brake lever
2. Locknut
3. Brake lever position adjusting bolt
4. Distance between brake lever and handlebar grip
1
4
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WARNING
EWB00221Always set the parking brake before starting
the engine. The ATV could start moving un-
expectedly if the parking brake is not ap-
plied. This could cause loss of control or a
collision.
 Always be sure you have released the park-
ing brake before you begin to ride. The brake
could overheat if you ride the ATV without re-
leasing the parking brake. You could lose braking performance which could cause an
accident. You could also wear out the brakes
prematurely.
EBU18532Shift pedalThe shift pedal is located on the left side of the en-
gine and is used in combination with the clutch
when shifting. (See page 7-2.)
1. Parking brake lever (unlocked position)
1. Shift pedal
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EBU37980Fuel tank capRemove the fuel tank cap by turning it counter-
clockwise.
WARNING
EWB02522Gasoline and gasoline vapors are extremely
flammable. To avoid fires and explosions and
to reduce the risk of injury when refueling, fol-
low these instructions. 1. Before refueling, turn off the engine and besure that no one is sitting on the vehicle. Nev-
er refuel while smoking, or while in the vicinity of sparks, open flames, or other sources of
ignition such as the pilot lights of water heat-
ers and clothes dryers.
2. Do not overfill the fuel tank. When refueling, be sure to insert the pump nozzle into the fuel
tank filler hole. Stop filling when the fuel
reaches the bottom of the filler tube. Because
fuel expands when it heats up, heat from the
engine or the sun can cause fuel to spill out of
the fuel tank.1. Fuel tank cap
1
1. Maximum fuel level
2. Fuel tank filler tube
2
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3. Wipe up any spilled fuel immediately.
NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00982]
4. Turn the fuel tank cap fully clockwise to make sure it is securely closed.EBU38170FuelMake sure there is sufficient gasoline in the tank
before starting off. Refuel if necessary.
WARNING
EWB02532Gasoline is poisonous and can cause injury or
death. Handle gasoline with care. Never siphon
gasoline by mouth. If you should swallow some
gasoline or inhale a lot of gasoline vapor, or get
some gasoline in your eyes, see your doctor
immediately. If gasoline spills on your skin,
wash with soap and water. If gasoline spills on
your clothing, change your clothes.
TIPConfirm the gasoline pump nozzle has the same
fuel identification mark. Recommended fuel:Premium unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity: 10 L (2.6 US gal, 2.2 Imp.gal)
Fuel reserve amount: 3.4 L (0.90 US gal, 0.75 Imp.gal)1. EN228 fuel identification mark
1
E5
E10
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5-11
5
To install the seat
Insert the projections on the front of the seat into
the seat holders, and then push down on the seat
at the rear to lock it in place. Make sure that the
seat is securely fitted.
EBU30055Front shock absorbers The shock absorber spring preload, rebound
damping force, and compression damping force
(fast and slow compression damping) can be ad-
justed.
WARNING
EWB02492
Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the
rebound damping force adjusting screw or
the oil reservoir with your bare hand or skin
until suspension components have cooled.
 Always adjust the shock absorber assem-
blies on the left and right side to the same
setting. Uneven adjustment can cause poor
handling and loss of stability, which could
lead to an accident. Notes on adjusting the suspension
A special wrench can be obtained at a Yamaha
dealer to make the spring preload adjustment.
 When adjusting the damping force settings, turn
the adjuster in direction (a) until it stops, and
then count the turns or clicks in direction (b).
 Although a damping force adjuster may turn or
click beyond the stated minimum settings, such
adjustments are ineffective and may damage
the suspension.
1. Projection
2. Seat holder
1
2
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Slow compression damping force
Turn the slow compression damping force adjust-
ing screw in direction (a) to increase the slow com-
pression damping force. Turn in direction (b) to
decrease the slow compression damping force.
WARNING
EWB00411These shock absorber assemblies contain
highly pressurized nitrogen gas. Read and un-
derstand the following information before han-
dling the shock absorber assemblies.

Do not tamper with or attempt to open the
cylinder assemblies.
 Do not subject the shock absorber assem-
blies to an open flame or other high heat
source. This may cause the unit to explode
due to excessive gas pressure.
 Do not deform or damage the cylinders in
any way. Cylinder damage will result in poor
damping performance.
 Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service. EBU30147Rear shock absorberThe shock absorber spring preload, rebound
damping force, and compression damping force
(fast and slow compression damping) can be ad-
justed.
1. Slow compression damping force adjusting screwSlow compression damping force settings:
Minimum (soft):20 click(s) in direction (b)
Standard: 7 click(s) in direction (b)
Maximum (hard): 1 click(s) in direction (b)
(a)
(b)
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WARNING
EWB02681Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the
rebound damping force adjusting screw or the
oil reservoir with your bare hand or skin until
the suspension components have cooled. Notes on adjusting the suspension
A special wrench can be obtained at a Yamaha
dealer to make the spring preload adjustment.
 When adjusting the damping force settings, turn
the adjuster in direction (a) until it stops, and
then count the turns or clicks in direction (b).
 Although a damping force adjuster may turn or
click beyond the stated minimum settings, such
adjustments are ineffective and may damage
the suspension.NOTICEECB00091Never turn an adjusting mechanism beyond
the minimum and maximum settings.
Spring preload
1. Elevate the vehicle and place a suitable stand under the frame.
2. Remove the cowling. (See page 9-10.)
3. Remove the clip from the hose holder, re- move the bolt, and then move the blow-by
gas chamber away from the vehicle.
4. Loosen the clamp screw at the air filter case side.1. Hose holder
2. Clip
3. Bolt
4. Blow-by gas chamber
2 3
4
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