2007 YAMAHA YFZ450 warning

4-17
1
2
34
5
6
7
8
9
10
11

weight and the riding conditions.
WARNING

EWB00430
This shock absorber assembly contains highly
pressurized nitrogen gas. Read and under-
stand the following information before han-
dling the shock absorber assembly.

Do not tamper with or attempt to open the
cylinder assembly.

Do not subject the shock absorber assembly
to an open flame or other high heat source.
This may cause the unit to explode due to ex-
cessive gas pressure.

Do not deform or damage the cylinder in any
way. Cylinder damage will result in poor
damping performance.

Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
Spring preload
1. Remove the seat. (See page 4-11.)
2. Loosen the clamp screw at the carburetor
side, and then disconnect the air intake duct.3. Disconnect the hose, and then remove the air
filter case by removing the bolts.
1. Clamp screw
1

4-21
1
2
34
5
6
7
8
9
10
11

to the standard setting.
Compression damping force
1. Remove the seat. (See page 4-11.)
2. Turn the adjusting screw in direction (a) to in-
crease the compression damping force and
thereby harden the damping, and in direction
(b) to decrease the compression damping
force and thereby soften the damping.CAUTION:
ECB00090
Never turn an adjusting mechanism beyond
the minimum and maximum settings.
NOTE:

Make sure that the position indicator marks are
aligned when the shock absorber assembly is set
to the standard setting.
3. Install the seat.WARNING

EWB00440
Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting screw or the oil reser-
voir with your bare hand or skin until suspen-
1. Compression damping force adjusting screw
2. Position indicator marks
(a)
(b)1
2

Compression damping setting:
Minimum (soft):
Adjusting screw fully turned out
Standard:
Adjusting screw 1 3/4 turns out from the
fully turned in position
Maximum (hard):
Adjusting screw fully turned in

5-3
1
2
3
45
6
7
8
9
10
11
WARNING

EWB00480
Always inspect your ATV each time you use it to make sure it is in safe operating condition.
Always follow the inspection and maintenance procedures and schedules described in the Owner’s
Manual. Failure to inspect increases the possibility of an accident or equipment damage.

5-4
1
2
3
45
6
7
8
9
10
11

EBU19540
Fuel
Make sure that there is sufficient fuel in the tank.
(See page 4-8.)
WARNING

EWB00520

Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.

Be careful not to spill fuel, especially on the
engine or exhaust pipe which can cause a
fire and severe injury. Wipe up any spilled
fuel immediately.

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

Be sure the fuel tank cap is closed securely.
EBU19560
Engine oil
Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-13.)
EBU19630
Coolant
Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-19.)
NOTE:

The coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.
WARNING

EWB00510
Wait for the engine and radiator to cool before
removing the radiator cap. You could be
burned by hot fluid and steam blown out under
pressure. Always put a thick rag over the cap
when opening. Allow any remaining pressure
to escape before completely removing the cap.
EBU19690
Front and rear brakes
Brake levers and brake pedal

Check for correct free play in the brake levers
and brake pedal. If the free play is incorrect,
have a Yamaha dealer check the brake system.
(See pages 8-34 and 8-35.)

Check the operation of the brake levers and
brake pedal. They should move smoothly and
there should be a firm feeling when the brakes
are applied. If not, have the ATV checked by a
Yamaha dealer.

5-5
1
2
3
45
6
7
8
9
10
11

Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-31.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or master cylinder. Apply the brakes
firmly for one minute. If there is any leaking, have
the ATV checked by a Yamaha dealer.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brake pads for wear. (See page 8-30.)
WARNING

EWB00580
Always check the brakes at the start of every
ride. Do not ride the ATV if you find any prob-
lem with the brakes or you could lose braking
ability, which could lead to an accident. If a
problem cannot be corrected by the adjust-
ment procedures provided in this manual, have
a Yamaha dealer check for the cause.
EBU19761
Throttle lever
Check the operation of the throttle lever. It must
open smoothly and spring back to the idle position
when released. Have a Yamaha dealer correct if
necessary.
EBU19770
Drive chain
Check the condition of the drive chain and check
the drive chain slack. Lubricate and adjust the
drive chain as necessary. (See page 8-39.)
EBU19791
Tires
WARNING

EWB00601
Use of improper tires on this ATV, or operation
of this ATV with improper or uneven tire pres-
sure, may cause loss of control, increasing
your risk of accident.
Pay attention to the following.

The tires listed below have been approved
by Yamaha Motor Co., Ltd. for this model.
Other tire combinations are not recommend-
Recommended brake fluid:
DOT 4

6-1
1
2
3
4
56
7
8
9
10
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:

6-4
1
2
3
4
56
7
8
9
10
11
CAUTION:

ECB00200
Always close the throttle before shifting gears,
otherwise damage to the engine and drive train
may result.
2. Pull the clutch lever to disengage the clutch.
3. Shift into first gear.
4. Open the throttle gradually and at the same
time, release the clutch lever slowly.
5. Once the ATV has attained adequate speed,
release the throttle, and at the same time,
quickly pull in the clutch lever.
6. Shift the transmission into second gear.
(Make sure not to shift the transmission into
neutral)
7. Open the throttle part way and gradually re-
lease the clutch lever.
8. Follow the same procedure when shifting to
the next higher gear.
WARNING

EWB00730
Opening the throttle abruptly or releasing the
clutch lever too quickly could make the ATV
wheelie, which would increase the chance of
an accident, including an overturn.
EBU20650
To decelerate
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. As
you slow down, shift to a lower gear. Be sure that
the engine has sufficiently slowed before engaging
a lower gear. Improper use of the brakes or shifting
can cause the tires to lose traction, reducing con-
trol and increasing the possibility of an accident.WARNING

EWB00710
Make sure the engine has sufficiently slowed
before shifting to a lower gear. Engaging a low-
er gear when the engine speed is too high
could make the wheels stop rotating and lose
traction. This could cause loss of control, an
accident and injury. It could also cause engine
or drive train damage.
CAUTION:

ECB00180

Even with the transmission in the neutral po-
sition, do not coast for long periods of time
with the engine off, and do not tow the ATV
for long distances. The transmission is prop-
erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage

6-6
1
2
3
4
56
7
8
9
10
11

EBU20860
Parking on a slope
WARNING

EWB00850
Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, place the ATV transversely across the
incline, shift into first gear, stop the engine, ap-
ply the parking brake, and then block the front
and rear wheels with rocks or other objects.
Do not park the ATV at all on hills that are so
steep you could not walk up them easily.
1. Bring the ATV to a stop by applying the brakes
in first gear.
2. Stop the engine and release the clutch lever.
3. With the rear brake applied, apply the parking
brake and slowly release the brake pedal.
EBU20910
Accessories and loading
EBU20920
Accessories
Accessories can affect the handling and control of
your ATV. Keep the following in mind when consid-
ering an accessory or operating an ATV which has
accessories.
1. Locked position
1