Page 9 of 166

OPERATION .................................................. 6-1
Starting a cold engine ................................ 6-1
Starting a warm engine .............................. 6-3
Operating the drive select lever and
driving in reverse ...................................... 6-3
Engine break-in .......................................... 6-5
Parking ....................................................... 6-5
Parking on a slope ..................................... 6-6
Accessories and loading ............................ 6-6
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............................... 7-17
CROSSING THROUGH SHALLOW
WATER ................................................... 7-18
RIDING OVER ROUGH TERRAIN ........... 7-21
SLIDING AND SKIDDING ......................... 7-21
WHAT TO DO IF... .................................... 7-23
WHAT TO DO... ........................................ 7-23PERIODIC MAINTENANCE AND
ADJUSTMENT................................................8-1
Owner’s manual and tool kit .......................8-1
Periodic maintenance chart for the
emission control system ...........................8-3
General maintenance and lubrication
chart ..........................................................8-5
Removing and installing panels ..................8-9
Checking the spark plug ...........................8-14
Engine oil and oil filter cartridge ................8-17
Final gear oil .............................................8-21
Differential gear oil ....................................8-24
Coolant .....................................................8-26
Cleaning the air filter element ...................8-30
Cleaning the spark arrester ......................8-33
V-belt cooling duct check hose .................8-35
V-belt case drain plug ...............................8-35
Adjusting the carburetor ............................8-36
Adjusting the engine idling speed .............8-36
Adjusting the throttle cable free play .........8-37
Valve clearance ........................................8-38
Adjusting the drive select lever safety
system cable ...........................................8-38
Brakes .......................................................8-38
Checking the front brake pads and rear
brake friction plates .................................8-39
Checking the brake fluid level ...................8-40U37S61E0.book Page 2 Tuesday, June 2, 2009 10:33 AM
Page 10 of 166

Changing the brake fluid .......................... 8-41
Checking the front brake lever free
play ......................................................... 8-41
Adjusting the brake pedal and rear brake
lever free play and checking the brake
pedal position ......................................... 8-42
Axle boots ................................................ 8-45
Brake light switches ................................. 8-46
Checking and lubricating the cables ........ 8-47
Checking and lubricating the front and
rear brake levers .................................... 8-47
Checking and lubricating the brake
pedal ...................................................... 8-48
Checking the wheel hub bearings ............ 8-49
Lubricating the drive shaft universal
joint ......................................................... 8-49
Checking the stabilizer bushes ................ 8-50
Lubricating the rear knuckle pivots ........... 8-50
Lubricating the steering shaft ................... 8-50
Battery ...................................................... 8-51
Replacing a fuse ...................................... 8-53
Replacing a headlight bulb ....................... 8-55
Adjusting a headlight beam ...................... 8-57
Replacing the tail/brake light bulb ............ 8-57
Removing a wheel .................................... 8-59
Installing a wheel ...................................... 8-59
Troubleshooting ....................................... 8-61Troubleshooting charts .............................8-62
CLEANING AND STORAGE ..........................9-1
Cleaning ......................................................9-1
Storage .......................................................9-2
SPECIFICATIONS .......................................10-1
CONSUMER INFORMATION.......................11-1
Identification numbers ...............................11-1
U37S61E0.book Page 3 Tuesday, June 2, 2009 10:33 AM
Page 11 of 166
1-1
1
EBU29680
LOCATION OF THE WARNING AND SPECIFICATION LABELS
EBU27153Read 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
67 8 11
9
10
U37S61E0.book Page 1 Tuesday, June 2, 2009 10:33 AM
Page 12 of 166
1-2
1
37S-F817R-00< 40 kg
( 88 lbs)
25.0 kPa
0.25 kgf/cm²
3.6 psi25.0 kPa
0.25 kgf/cm²
3.6 psi
5FU-F816M-M0
1P0-F816P-20
37S-F817R-10< 80 kg
( 176 lbs)
< 5880 N< 600 kgf< 1322 lbf
< 147 N
< 15 kgf
< 33 lbf
37S-F817S-00
13
2
4
5U37S61E0.book Page 2 Tuesday, June 2, 2009 10:33 AM
Page 13 of 166
1-3
1
1P0-F816R-00
1P0-F816L-20
67
8
U37S61E0.book Page 3 Tuesday, June 2, 2009 10:33 AM
Page 14 of 166
1-4
1
37S-F816N-00< 0.5 kg
( 1 lb )
37S-F816S-00
YEAR OF CONSTRUCTION : 2009
MODEL : YFM450FWAN
MAX.POWER : 19.4 kWMASS IN RUNNING ORDER : 285 kg
YAMAHA MOTOR CO., LTD.
2500 SHINGAI, IWATA, JAPAN
37S-F155A-10
9
10
11U37S61E0.book Page 4 Tuesday, June 2, 2009 10:33 AM
Page 15 of 166

1-5
1 Familiarize yourself with the following pictograms and read the explanatory text, then make sure to check
the pictograms that apply to your model.
Read the Owner’s manual.
ALWAYS use an approved helmet and
protective gear.
NEVER permit children under age 6 to
operate this ATV.
Operation of this ATV by children under the
age of 6 increases the risk of severe injury
or death.
Adult supervision required for children under
age 16.
NEVER permit children under age 10 to
operate this ATV.
Operation of this ATV by children under the
age of 10 increases the risk of severe injury
or death.
Adult supervision required for children under
age 16.NEVER permit children under age 12 to
operate this ATV.
Operation of this ATV by children under the
age of 12 increases the risk of severe injury
or death.
Adult supervision required for children under
age 16.
NEVER operate this ATV if you are under
age 16.
Operating this ATV if you are under the age
of 16 increases your chance of severe injury
or death.
NEVER use on paved roads.
NEVER carry passengers.
U37S61E0.book Page 5 Tuesday, June 2, 2009 10:33 AM
Page 16 of 166

1-6
1
**.* kPa
*.** kgf/cm²
*.* psi**.* kPa
*.** kgf/cm²
*.* psi
NEVER use with drugs or alcohol.
NEVER store fuel or flammable liquids.
This unit contains high-pressure nitrogen
gas.
Mishandling can cause explosion. Do not
incinerate, puncture or open.
Use unleaded gasoline only.
Measure tire pressure when tires are cold.Adjust tire pressure.
Improper tire pressure can cause loss of
control.
Loss of control can result in severe injury or
death.
Turning the ATV in 4WD-LOCK
(“DIFF.LOCK”) takes more effort.
Operate at a slow speed and allow extra
time and distance for maneuvers to avoid
loss of control.
This pictogram shows the loading limits
and/or maximum load capacity for this ATV.
Follow all load limits and other loading
guidelines in this manual.
Load may include the driver, passenger,
human protective gear, accessories, goods,
luggage, and all other load related items.
Make sure you do not exceed the load limits.
Overloading can cause loss of control.
Loss of control can result in severe injury or
death.
U37S61E0.book Page 6 Tuesday, June 2, 2009 10:33 AM