Page 3 of 154
READ THIS MANUAL CAREFULLY!
It contains important safety information.
WARNING
OWNER’S MANUAL
YFZ450D
This ATV should not be ridden by anyone under 16 years of age.
1PD-28199-61-E0
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EBU17170
INTRODUCTION
EBU17322Congratulations on your purchase of the Yamaha YFZ450D. This ATV represents the result of many years
of Yamaha experience in the production of fine sporting, touring, and pacesetting racing machines. With the
purchase of this Yamaha, you can now appreciate the high degree of craftsmanship and reliability that have
made Yamaha a leader in these fields.
This manual will provide you with a good basic understanding of the features and operation of this ATV.
This manual includes important safety information. It provides information about special tech-
niques and skills necessary to ride the ATV. It also includes basic maintenance and inspection proce-
dures. If you have any questions regarding the operation or maintenance of your ATV, please consult a
Yamaha dealer.
AN IMPORTANT SAFETY MESSAGE:●Read this manual completely before operating your ATV. Make sure you understand all instructions.●Pay close attention to the warning and notice labels on the ATV.●This ATV should not be ridden by anyone under 16 years of age.●This ATV is a high-performance ATV for off-road use only, for sport-type recreational and competitive use
by experienced operators.
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EBU17330
IMPORTANT MANUAL INFORMATION
EBU17342FAILURE TO FOLLOW THE WARNINGS CONTAINED IN THIS MANUAL CAN RESULT IN SERIOUS IN-
JURY OR DEATH.
Particularly important information is distinguished in this manual by the following notations:
* Product and specifications are subject to change without notice.This is the safety alert symbol. It is used to alert you to potential per-
sonal injury hazards. Obey all safety messages that follow this sym-
bol to avoid possible injury or death.
A WARNING indicates a hazardous si
tuation which, if not avoided,
could result in death or serious injury.
A NOTICE indicates special precautions that must be taken to avoid
damage to the vehicle or other property.
A TIP provides key information to make procedures easier or clearer.
WARNING
NOTICETIPU1PD61E0.book Page 1 Tuesday, February 14, 2012 10:06 AM
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EBU17420
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS ............................ 1-1
SAFETY INFORMATION .............................. 2-1
DESCRIPTION .............................................. 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments ............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS .................................................. 4-1 Main switch ................................................ 4-1
Indicator light and warning light .................. 4-2
Handlebar switches .................................... 4-3
Throttle lever .............................................. 4-3
Speed limiter .............................................. 4-4
Clutch lever ................................................ 4-5
Brake lever ................................................. 4-5
Brake pedal ................................................ 4-6
Parking brake lever .................................... 4-6
Shift pedal .................................................. 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................ 4-8 Fuel cock ..................................................4-10
Starter (choke) ..........................................4-11
Seat ..........................................................4-12
Adjusting the front shock absorber
assemblies ..............................................4-13
Adjusting the rear shock absorber assembly .................................................4-14
PRE-OPERATION CHECKS ..........................5-1 Fuel .............................................................5-4
Engine oil ....................................................5-4
Coolant .......................................................5-4
Front and rear brakes .................................5-4
Throttle lever ...............................................5-5
Drive chain ..................................................5-5
Tires ............................................................5-5
Chassis fasteners .......................................5-7
Instruments, lights and switches .................5-7
OPERATION...................................................6-1 Starting a cold engine .................................6-1
Starting a warm engine ...............................6-3
Shifting ........................................................6-3
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1-1
1
EBU29680
LOCATION OF THE WARNING AND SPECIFICATION LABELS
EBU29992Read and understand all of the labels on your ATV. These labels contain important information for safe and
proper operation.
Never remove any labels from your ATV. If a label becomes difficult to read or comes off, request a replace-
ment label from your Yamaha dealer.
For Europe
3
12 45 8
6,7
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1-9
1
4AA-22259-40WARNING
OPERATING TIRE PRESSURE : Set with tires cold
Recommended
: Front
: 27.5
kPa
Rear
: 30.0
kPa
Minimum
: Front
: 24.5
kPa
Rear
: 27.0
kPa
Never set tire pressure below minimum.
It could cause the tire to dislodge from the rim.LOADINGMaximum weight capacity :
100 kg (220 lbs.)
Includes weight of operator, cargo and accessories.Improper tire pressure or overloading can cause
loss of control.
Loss of control can result in severe injury or
death.
4.0 psi
4.4 psi 3.6 psi
4.0 psi(
( )
() () )
5D3-2816M-00
WARNINGNEVER ride as a
passenger.Passengers can causea loss of control,resulting in SEVEREINJURY or DEATH.5FE-2151H-01
Use
97 octane
5TG-2415E-10
PREMIUM unleaded gasoline with min. (RON).
3
4 5
6
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2-6
2
WARNING
EWB00072Avoid Carbon Monoxide Poisoning
All engine exhaust contains carbon monoxide,
a deadly gas. Breathing carbon monoxide can
cause headaches, dizziness, drowsiness, nau-
sea, confusion, and eventually death.
Carbon Monoxide is a colorless, odorless,
tasteless gas which may be present even if you
do not see or smell any engine exhaust. Deadly
levels of carbon monoxide can collect rapidly
and you can quickly be overcome and unable
to save yourself. Also, deadly levels of carbon
monoxide can linger for hours or days in en-
closed or poorly ventilated areas. If you experi-
ence any symptoms of carbon monoxide
poisoning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREATMENT.●Do not run engine indoors. Even if you try to
ventilate engine exhaust with fans or open
windows and doors, carbon monoxide can
rapidly reach dangerous levels.●Do not run engine in poorly ventilated or par-
tially enclosed areas such as barns, garages,
or carports.
●Do not run engine outdoors where engine
exhaust can be drawn into a building
through openings such as windows and
doors.
WARNING
EWB02591When transporting the ATV in another vehicle,
be sure it is kept upright and that the fuel cock
is in the “OFF” position. Otherwise, fuel may
leak out of the carburetor or fuel tank.
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4-2
4
EBU17805Indicator light and warning light EBU17860Neutral indicator light “ ”
This indicator light comes on when the transmis-
sion is in the neutral position.EBU17930Coolant temperature warning light “ ”
This warning light comes on when the engine over-
heats. When this occurs during operation, stop the
engine as soon as it is safe to do so and allow it to
cool down for about 10 minutes.The electrical circuit of the warning light can be
checked according to the following procedure.
1. Set the engine stop switch to “ ” and turn the key to “ON”.
2. Shift the transmission into the neutral position or pull the clutch lever.
3. Push the start switch. If the warning light does not come on while the start switch is pushed,
have a Yamaha dealer check the electrical cir-
cuit.
NOTICEECB00010●The engine may overheat if the ATV is over-
loaded. In this case, reduce the load to spec-
ification.●Start the engine after making sure that the
warning light is out. Continuous use while
the warning light is on may cause damage to
the engine.
1. Neutral indicator light “N”
2. Coolant temperature warning light “ ”
1 2
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