2012 YAMAHA YFZ450 engine

EBU29121
Read this manual carefully before operating this vehicle. This manual should stay with this ve-
hicle if it is sold.
ANSI/SVIA 1-2010General Manager
RV Engineering Division
Recreational Vehicle Business Unit
Motorcycle Business Operations
YAMAHA MOTOR CO., LTD.
1 February, 2011
We, YAMAHA MOTOR CO., LTD. 2500 Shingai, Iwata, Japan,
declare in sole responsibility, that the product
(Make, model)
(If applicable)
and to the other relevant Directives of EEC
2004/108/EC
(Title and/or number and date of issue of the other Directives of EEC)
(If applicable)YAMAHA MOTOR EUROPE N.V.
Koolhovenlaan 101, 1119 NC Schiphol-Rijk, The Netherlands
Signature
Shinya Shimada
Date of Issue
to which this declaration applies, conforms to the essential health
and safety requirements of Directive 2006/42/EC
To effect correct application of the essential health and safety requirements
stated in the Directives of EEC, the following-standards and/or technical
specifications were consulted:
(Title and/or number and date of issue of standards and/or specifications)
Authorized Representative
EC Declaration of Conformity
conforming to Directive 2006/42/EC
YFZ450 (YFZ450) (JY4AJ60W0B0000001–)
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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
Engine break-in ...........................................6-5U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM

Parking ....................................................... 6-5
Parking on a slope ..................................... 6-6
Accessories and loading ............................ 6-7
RIDING YOUR ATV ...................................... 7-1 GETTING TO KNOW YOUR ATV............... 7-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 7-2
BE CAREFUL WHERE YOU RIDE ............. 7-9
TURNING YOUR ATV .............................. 7-12
CLIMBING UPHILL ................................... 7-13
RIDING DOWNHILL.................................. 7-16
CROSSING A SLOPE............................... 7-18
CROSSING THROUGH SHALLOW WATER ................................................... 7-19
RIDING OVER ROUGH TERRAIN ........... 7-20
SLIDING AND SKIDDING ......................... 7-21
WHAT TO DO IF... .................................... 7-22
WHAT TO DO... ........................................ 7-22
PERIODIC MAINTENANCE AND
ADJUSTMENT ............................................... 8-1 Owner’s manual and tool kit ....................... 8-2
Periodic maintenance chart for the emission control system ........................... 8-3
General maintenance and lubrication chart ......................................................... 8-5 Removing and installing the panel ..............8-9
Checking the spark plug ...........................8-10
Engine oil and oil filter element .................8-14
Coolant .....................................................8-20
Cleaning the air filter element ...................8-24
Cleaning the spark arrester ......................8-28
Adjusting the carburetor ............................8-30
Checking the engine idling speed .............8-30
Adjusting the throttle lever free play .........8-31
Valve clearance ........................................8-31
Brakes .......................................................8-32
Checking the front and rear brake pads ...8-32
Checking the brake fluid level ...................8-33
Changing the brake fluid ...........................8-36
Checking the front brake lever free play ...8-36
Checking the brake pedal height ..............8-36
Adjusting the parking brake free play .......8-37
Brake light switches ..................................8-38
Adjusting the clutch lever free play ...........8-39
Drive chain slack .......................................8-41
Lubricating the drive chain ........................8-43
Checking and lubricating the cables .........8-43
Checking and lubricating the brake and
clutch levers ............................................8-44
Checking the shift pedal ...........................8-45
Checking and lubricating the brake pedal .......................................................8-45
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2-1
2
EBU17431
SAFETY INFORMATION
EBU17594AN ATV IS NOT A TOY AND CAN BE HAZARD-OUS TO OPERATE.An ATV handles differently from other vehicles, in-
cluding motorcycles and cars. A collision or roll-
over can occur quickly, even during routine
maneuvers such as turning and riding on hills or
over obstacles, if you fail to take proper precau-
tions.
SEVERE INJURY OR DEATH can result if you do
not follow these instructions:
Read this manual and all labels carefully and fol-
low the operating procedures described.
Never operate an ATV without proper training or
instruction.
Always follow the age recommendation:
– A child under 16 years old should never oper-
ate an ATV with engine size greater than 90 cc.
Never allow a child under age 16 to operate an
ATV without adult supervision, and never allow
continued use of an ATV by a child if he or she
does not have the abilities to operate it safely.

Never carry a passenger on an ATV.
Always avoid operating an ATV on any paved
surfaces, including sidewalks, driveways, park-
ing lots and paved streets.
Never operate an ATV on any paved street,
paved road or motorway.
Watch carefully for other vehicles when operat-
ing on unpaved public streets or roads. Make
sure you know your country ’s laws and regula-
tions before you ride on unpaved public streets
or roads.
Never operate an ATV without wearing an ap-
proved motorcycle helmet that fits properly. You
should also wear eye protection (goggles or face
shield), gloves, boots, a long-sleeved shirt or a
jacket, and long pants.
Never consume alcohol or drugs before or while
operating this ATV.
Never operate at speeds too fast for your skills
or the riding conditions. Always go at a speed
that is proper for the terrain, visibility, operating
conditions, and your experience.
Never attempt wheelies, jumps, or other stunts.
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2-3
2speed 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 re-
duce the chance of skidding or sliding out of con-
trol.
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 modify an ATV through improper installa-
tion or use of accessories.
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.
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-
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2-4
2
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.U1PD60E0.book Page 4 Monday, June 13, 2011 2:57 PM

3-1
3
EBU17680
DESCRIPTION
EBU17690Left view
EBU17700Right view
1. Headlights
2. Fuel cock
3. Starter (choke)
4. Fuse
5. Tail/brake light
6. Coolant reservoir
7. Shift pedal
8. Engine oil tank
123 45
6
7
8
1. Spark arrester
2. Seat
3. Fuel tank cap
4. Radiator cap
5. Oil filter element
6. Brake pedal1
23
4
5
6
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4-1
4
EBU17733
INSTRUMENT AND CONTROL FUNCTIONS
EBU17760Main switch The positions of the main switch are as follows:
ON
All electrical systems are supplied with power. The
headlights and taillight come on when the light
switch is on, and the engine can be started. The
key cannot be removed.
OFF
All electrical systems are off. The key can be re-
moved.
1. Main switch
OFF ON
1
U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM