2007 YAMAHA YFZ450 check engine light

EBU17420
TABLE OF CONTENTS
SAFETY INFORMATION .............................. 1-1
LOCATION OF THE WARNING AND
SPECIFICATION LABELS ............................ 2-1
DESCRIPTION .............................................. 3-1
Left 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 ................................................ 4-6
Brake pedal ............................................... 4-6
Parking brake lever ................................... 4-6
Shift pedal ................................................. 4-7
Fuel tank cap ............................................. 4-8
Fuel ........................................................... 4-8
Fuel cock ................................................... 4-9Starter (choke) “ ” ................................. 4-11
Seat ......................................................... 4-11
Adjusting the front shock absorber
assemblies .............................................4-12
Adjusting the rear shock absorber
assembly ................................................4-16
PRE-OPERATION CHECKS ..........................5-1
Pre-operation check list ............................. 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
Measuring the tire pressure ....................... 5-6
Tire wear limit ............................................ 5-7
Chassis fasteners ...................................... 5-8
Instruments, lights and switches ................ 5-8
OPERATION...................................................6-1
Starting a cold engine ................................ 6-1
Starting a warm engine .............................. 6-3
Shifting ....................................................... 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
JUDGEMENT ...........................................7-2
BE CAREFUL WHERE YOU RIDE ............ 7-8
TURNING YOUR ATV ............................. 7-12
CLIMBING UPHILL .................................. 7-14
RIDING DOWNHILL................................. 7-16
CROSSING A SLOPE.............................. 7-17
CROSSING THROUGH SHALLOW
WATER ..................................................7-18
RIDING OVER ROUGH TERRAIN .......... 7-20
SLIDING AND SKIDDING ........................ 7-20
WHAT TO DO IF... ................................... 7-21
WHAT TO DO... ....................................... 7-21
PERIODIC MAINTENANCE AND MINOR
REPAIR .......................................................... 8-1
Owner’s manual and tool kit ...................... 8-1
Periodic maintenance and lubrication
chart ........................................................ 8-3
Removing and installing the panel ............ 8-8
Checking the spark plug ............................ 8-9
Engine oil and oil filter element ............... 8-13
Coolant .................................................... 8-19Cleaning the air filter element .................. 8-23
Cleaning the spark arrester ..................... 8-26
Adjusting the carburetor ........................... 8-28
Checking the engine idling speed ............ 8-29
Adjusting the throttle cable free play ........ 8-29
Valve clearance ....................................... 8-30
Checking the front and rear brake pads .. 8-30
Checking the brake fluid level .................. 8-31
Changing the brake fluid .......................... 8-34
Checking the front brake lever free play .. 8-34
Checking the brake pedal position ........... 8-35
Adjusting the parking brake free play ...... 8-36
Brake light switches ................................. 8-37
Adjusting the clutch lever free play .......... 8-38
Drive chain slack ...................................... 8-39
Lubricating the drive chain ....................... 8-41
Checking and lubricating the cables ........ 8-42
Checking and lubricating the brake and
clutch levers ........................................... 8-42
Checking and lubricating the brake and
shift pedals ............................................. 8-43
Checking the wheel bearings ................... 8-43
Lubricating the swingarm pivots .............. 8-44
Lubricating the upper and lower arm
pivots ..................................................... 8-44
Battery ..................................................... 8-45
Replacing the fuse ................................... 8-46
Replacing a headlight bulb ...................... 8-47
Adjusting a headlight beam ..................... 8-49

1-3
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2
3
4
5
6
7
8
9
10
11

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 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

EWB00061

Always turn off the engine when refueling.

Do not refuel right after the engine has been
running and is still very hot.

Do not spill gasoline on the engine or ex-
haust pipe/muffler when refueling. Never re-
fuel while smoking, or in the vicinity of
sparks, open flames, or other sources of ig-
nition such as the pilot lights of water heat-
ers and clothes dryers. Gasoline can catch
fire and you could be burned.

When transporting the ATV in another vehi-
cle, be sure it is kept upright and that the fuel

4-2
1
2
34
5
6
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8
9
10
11

EBU17802
Indicator light and warning light
EBU17860
Neutral indicator light “”
This indicator light comes on when the transmis-
sion is in the neutral position.
EBU17930
Coolant 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.
CAUTION:

ECB00010

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 “ ”
12

6-1
1
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3
4
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11

EBU19880
OPERATION
EBU19900
Read the Owner’s Manual carefully before riding
the ATV.
WARNING

EWB00630
Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury. If there is a control or func-
tion you do not understand, ask your Yamaha
dealer.
EBU20101
Starting a cold engine
WARNING

EWB00640
Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-
dent or collision.
CAUTION:

ECB00150
See the “Engine break-in” section on page 6-5
prior to operating the engine for the first time.
1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON” and the engine
stop switch to “RUN”.
4. Shift the transmission into neutral. The neutral
indicator light should come on. If the indicator
light does not come on, have a Yamaha deal-
er check the electrical circuit.
NOTE:

This model is equipped with an ignition circuit cut-
off system. The engine can be started under the
following conditions.

The transmission is in neutral.

The clutch is disengaged with the transmission
in gear. However, it is recommended to shift into
neutral before starting the engine.
5. Use the starter (choke) in reference to the fig-
ure:

8-6
1
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3
4
5
6
78
9
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11

25 Engine oil

Change.

Check ATV for oil leakage, and correct if neces-
sary.
√ √√√
26Engine oil filter ele-
ment

Replace.
√√√
27 Cooling system

Check coolant level and ATV for coolant leakage,
and correct if necessary.
√√√√√

Replace coolant. Every 2 years
28
*
Moving parts and
cables

Lubricate.
√√√√
29
*
Throttle lever hous-
ing and cable


Check operation and correct if necessary.

Check throttle cable free play and adjust if neces-
sary.

Lubricate throttle lever housing and cable.
√√√√√
30
*
Exhaust system

Check for leakage and replace gasket(s) if neces-
sary.

Check for looseness and tighten all screw clamps
and joints if necessary.
√√√
31 Spark arrester

Clean.
√√√
32
*
Front and rear brake
switches


Check operation and correct if necessary.
√√√√√
33
*
Lights and switches


Check operation and correct if necessary.

Adjust headlight beams.
√√√√√
NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth 1 3 6 6 12
km
(mi)320
(200)1200
(750)2400
(1500)2400
(1500)4800
(3000)
hours 20 75 150 150 300

8-12
1
2
3
4
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6
78
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kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
NOTE:

If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
1

Specified spark plug:
NGK/CR8E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
1. Spark plug gap

INDEX
A
Accessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-23
B
Battery .......................................................................... 8-45
Brake and clutch levers, checking and lubricating ....... 8-42
Brake and shift pedals, checking and lubricating ......... 8-43
Brake fluid, changing.................................................... 8-34
Brake fluid level, checking............................................ 8-31
Brake lever ..................................................................... 4-6
Brake lever free play, checking the front ...................... 8-34
Brake light switches ..................................................... 8-37
Brake pads, checking the front and rear ...................... 8-30
Brake pedal .................................................................... 4-6
Brake pedal position, checking .................................... 8-35
Brakes, front and rear .................................................... 5-4
C
Cables, checking and lubricating ................................. 8-42
Carburetor, adjusting.................................................... 8-28
Chassis fasteners........................................................... 5-8
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-5
Clutch lever free play, adjusting ................................... 8-38
Coolant ................................................................. 5-4
,
8-19
Coolant temperature warning light ................................. 4-2
D
Drive chain ..................................................................... 5-5
Drive chain, lubricating ................................................. 8-41
Drive chain slack .......................................................... 8-39
E
Engine break-in .............................................................. 6-5
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-29
Engine oil ....................................................................... 5-4
Engine oil and oil filter element .................................... 8-13
Engine, starting a warm ................................................. 6-3
Engine stop switch ......................................................... 4-3
F
Fuel ........................................................................ 4-8
,
5-4
Fuel cock ........................................................................ 4-9
Fuel tank cap.................................................................. 4-8
Fuse, replacing............................................................. 8-46
H
Handlebar switches ........................................................ 4-3
Headlight beam, adjusting............................................ 8-49
Headlight bulb, replacing.............................................. 8-47
I
Identification numbers .................................................. 11-1
Indicator light and warning light...................................... 4-2
Instruments, lights and switches .................................... 5-8