2021 YAMAHA YFZ450R brake

EBU17421
TABLE OF CONTENTS
VEHICLE IDENTIFICATION ............................ 1-1Identification numbers ................................ 1-1
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 2-1
SAFETY INFORMATION ................................ 3-1
DESCRIPTION................................................ 4-1 Left view ...................................................... 4-1
Right view.................................................... 4-1
Controls and instruments............................ 4-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 5-1 Main switch ................................................. 5-1
Indicator light and warning lights ................ 5-1
Handlebar switches .................................... 5-3
Throttle lever ............................................... 5-4
Speed limiter ............................................... 5-4
Clutch lever ................................................. 5-5
Brake lever .................................................. 5-5
Brake pedal ................................................. 5-6
Parking brake lever ..................................... 5-6 Shift pedal................................................... 5-7
Fuel tank cap .............................................. 5-8
Fuel ............................................................. 5-9
Seat .......................................................... 5-10
Front shock absorbers ............................ 5-11
Rear shock absorber ................................ 5-15
Handlebar position ................................... 5-23
PRE-OPERATION CHECKS .......................... 6-1 Fuel ............................................................. 6-4
Engine oil .................................................... 6-4
Coolant ....................................................... 6-4
Front and rear brakes ................................. 6-4
Throttle lever ............................................... 6-5
Drive chain .................................................. 6-5
Tires ............................................................ 6-5
Chassis fasteners ....................................... 6-7
Instruments, lights and switches ................ 6-7
OPERATION .................................................. 7-1 Starting the engine ..................................... 7-1
Shifting........................................................ 7-2
Engine break-in........................................... 7-4
Parking........................................................ 7-4UBKD60E0.book Page 1 Wednesday, November 18, 2020 8:39 AM

Parking on a slope ...................................... 7-5
Accessories and loading ............................. 7-5
RIDING YOUR ATV ........................................ 8-1 GETTING TO KNOW YOUR ATV ................ 8-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 8-2
BE CAREFUL WHERE YOU RIDE ............... 8-8
TURNING YOUR ATV................................ 8-11
CLIMBING UPHILL ................................... 8-13
RIDING DOWNHILL .................................. 8-16
CROSSING A SLOPE................................ 8-17
CROSSING THROUGH SHALLOW WATER .................................................... 8-18
RIDING OVER ROUGH TERRAIN ............. 8-20
SLIDING AND SKIDDING.......................... 8-20
WHAT TO DO IF... ..................................... 8-21
PERIODIC MAINTENANCE AND
ADJUSTMENT................................................ 9-1 Owner’s Manual and tool kit ....................... 9-2
Periodic maintenance chart: Emission control system .......................................... 9-3
Periodic maintenance chart: General maintenance and lubrication..................... 9-5
Removing and installing the cowling and panels...................................................... 9-10 Checking the spark plug........................... 9-13
Engine oil and oil filter element................. 9-14
Why Yamalube ......................................... 9-20
Coolant ..................................................... 9-20
Cleaning the air filter element ................... 9-22
Cleaning the spark arrester ...................... 9-26
Adjusting the throttle lever free play ......... 9-28
Valve clearance......................................... 9-28
Brakes....................................................... 9-28
Checking the front and rear brake pads... 9-29
Checking the brake fluid level .................. 9-30
Changing the brake fluid .......................... 9-31
Checking the front brake lever free play... 9-32
Checking the brake pedal height.............. 9-32
Adjusting the parking brake free play ....... 9-33
Brake light switches ................................. 9-34
Adjusting the clutch lever free play .......... 9-35
Drive chain slack....................................... 9-36
Lubricating the drive chain ....................... 9-38
Checking and lubricating the cables ........ 9-38
Checking and lubricating the brake and
clutch levers ........................................... 9-39
Checking the shift pedal ........................... 9-40
Checking and lubricating the brake pedal ....................................................... 9-40
Checking the wheel hub bearings ............ 9-40
Lubricating the swingarm pivots .............. 9-41
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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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3-3
3
technique described in this manual on level
ground. Avoid crossing the side of a steep hill if
possible.
 Always use proper procedures if you stall or roll
backwards when climbing a hill. To avoid stall-
ing, use the proper gear and maintain a steady
speed when climbing a hill. If you stall or roll
backwards, follow the special procedure for
braking described in this manual. Dismount on
the uphill side or to a side if pointed straight up-
hill. Turn the ATV around and remount, following
the procedure described in this manual.
 Always check for obstacles before operating in
a new area.
 Never attempt to operate over large obstacles,
such as large rocks or fallen trees. Always follow
proper procedures when operating over obsta-
cles as described in this manual.
 Always be careful when skidding or sliding.
Learn to safely control skidding or sliding by
practicing at low speeds and on level, smooth
terrain. On extremely slippery surfaces, such as
ice, go slowly and be very cautious in order to
reduce the chance of skidding or sliding out of
control. 
Never operate an ATV in fast flowing water or in
water deeper than that recommended in this
manual. Remember that wet brakes may have
reduced stopping ability. Test your brakes after
leaving water. If necessary, apply them several
times to let friction dry out the linings.
 Always use the size and type of tires specified in
this manual.
 Always maintain proper tire pressure as de-
scribed in this manual.
 Never exceed the stated load capacity for an
ATV. Cargo should be properly distributed and
securely attached. Reduce speed and follow in-
structions in this manual for carrying cargo or
pulling a trailer. Allow greater distance for brak-
ing.
 Do not operate your ATV during darkness un-
less it is equipped with a properly functioning
headlight. Off-road riding is inherently danger-
ous and additionally, off-road trails do not have
streetlights to guide you.
 Never maintain an ATV without proper knowl-
edge. Contact an authorized ATV dealer to in-
form you on basic ATV maintenance. Certain
maintenance can only be carried out by certified
staff.
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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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4-2
4
EBU17715Controls and instruments1. Clutch lever
2. Parking brake lever
3. Handlebar switches
4. Main switch
5. Front brake fluid reservoir
6. Throttle lever
7. Brake lever
2
1
3
6
5
4
7
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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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