2021 YAMAHA YFZ450R lock

5-4
5starter will not have enough power to crank the
engine. If this should happen, remove the bat-
tery and recharge it. (See page 9-43.)
EBU18286Throttle leverPush the throttle lever to increase engine speed.
Spring tension returns the lever to the rest position
when released. Always check that the throttle le-
ver returns normally before starting the engine.
EBU18325Speed limiterThe speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum.
Adjusting the speed limiter1. Loosen the locknut.
2. To increase the maximum engine power
available and the maximum speed of the ATV,
turn the adjusting screw in direction (a). To
decrease the maximum engine power avail-
able and the maximum speed of the ATV, turn
1. Throttle lever
1
1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
3
12
(a)
(b)
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5-5
5
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
23
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5-6
5The brake lever is located on the right side of the
handlebar. To apply the front brake, pull the brake
lever toward the handlebar grip.
The brake lever is equipped with a position adjust-
ing bolt. To adjust the distance between the brake
lever and the handlebar grip, hold the brake lever
away from the handlebar so it does not contact
the adjusting bolt, loosen the locknut, turn the ad-
justing bolt, and then tighten the locknut.
EBU18434Brake pedal
The brake pedal is located on the right side of the
ATV. To apply the rear brake, push down on the
brake pedal.EBU18521Parking brake leverUse the parking brake before starting the engine
or parking the ATV, especially on a slope. To apply
the parking brake, move the parking brake lever in
direction (a). To release the parking brake, move
the parking brake lever in direction (b).
1. Brake pedal
1
1. Parking brake lever (locked position)
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5-7
5
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
1
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5-8
5
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
1
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5-9
5
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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5-10
5About the recommended fuel
Use RON 97 octane or higher. If knocking or ping-
ing occurs, try a different brand or higher octane
gasoline. Gasoline containing ethanol can be used
if the ethanol content does not exceed 10% (E10).
Gasoline containing methanol is not recommend-
ed because it can cause damage to the fuel sys-
tem or vehicle performance problems.
NOTICEECB00071Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.
EBU26734SeatTo remove the seat
Insert your hand between the rear of the seat and
the rear fender, pull the seat lock lever and pull up
the seat at the rear.1. Seat lock lever
1
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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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