YAMAHA YFZ450R 2012 Workshop Manual

5-2
5
Front brake
Check operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
 Check brake pads for wear, and replace if necessary.
 Check brake fluid level in reservoir, and add specified brake fluid to
specified level if necessary.
 Check hydraulic system for leakage. Correct if necessary. 5-4, 8-30, 8-32, 8-33
Rear brake 
Check operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
 Check brake pads for wear, and replace if necessary.
 Check brake fluid level in reservoir, and add specified brake fluid to
specified level if necessary.
 Check hydraulic system for leakage. Correct if necessary. 5-4, 8-30, 8-32, 8-34
Clutch 
Check operation, and correct if necessary.
 Lubricate cable if necessary.
 Check lever free play, and adjust if necessary. 8-36
Throttle lever 
Make sure that operation is smooth. Lubricate cable and lever hous-
ing if necessary.
 Check lever free play, and adjust if necessary. 5-5, 8-29
Control cables Make sure that operation is smooth. Lubricate if necessary. 8-40
Drive chain 
Check chain slack, and adjust if necessary.
 Check chain condition. Lubricate if necessary. 5-5, 8-38, 8-40
Wheels and tires 
Check wheel condition, and replace if damaged.
 Check tire condition and tread depth. Replace if necessary.
 Check air pressure. Correct if necessary. 5-5
Shift pedal 
Make sure that operation is smooth.
 Correct if necessary. 8-42
Brake pedal 
Make sure that operation is smooth. Lubricate pedal pivoting point if
necessary. 8-42
ITEM ROUTINE PAGE
U18P66E0.book Page 2 Monday, May 16, 2011 4:23 PM

5-3
5
Brake and clutch levers
Make sure that operation is smooth. Lubricate lever pivoting points if
necessary. 8-41
Chassis fasteners Make sure that all nuts, bolts and screws are properly tightened. 5-7
Instruments, lights and
switches 
Check operation, and correct if necessary. 5-7
ITEM ROUTINE PAGEU18P66E0.book Page 3 Monday, May 16, 2011 4:23 PM

5-4
5
EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-9.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-16.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-22.)TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU19712Front and rear brakes Brake lever and brake pedal
Check that there is no free play in the brake le-
ver. If there is free play, have a Yamaha dealer
check the brake system.

Check for correct brake pedal height. (See page
8-34.) If the pedal height is incorrect, have a
Yamaha dealer adjust it.
Check the operation of the lever and pedal. They
should move smoothly and there should be a
firm feeling when the brakes are applied. If not,
have a Yamaha dealer check the brake system.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-32.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If there is any leak-
age, have a Yamaha dealer check the brake sys-
tem.
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.) Specified brake fluid:
DOT 4
U18P66E0.book Page 4 Monday, May 16, 2011 4:23 PM

5-5
5
EBU19761Throttle 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.EBU19770Drive chain Check the condition of the drive chain and check
the drive chain slack. Lubricate and adjust the
drive chain as necessary. (See page 8-38.)EBU19794Tires Check tire pressure regularly to make sure it is at
the recommended specifications. Also check for
wear and damage.
Tire pressure
Use the low-pressure tire gauge to check and ad-
just tire pressures when the tires are cold. Tire
pressures must be equal on both sides.
WARNING! Operation of this vehicle with im- proper tire pressure may cause severe injury
or death from loss of control or rollover. Tire
pressure below the minimum specified could also cause the tire to dislodge from the rim un-
der severe riding conditions.
[EWB02541]
Set tire
pressures to the following specifications:
The low-pressure tire gauge is included as stan-
dard equipment. Make two measurements of the
tire pressure and use the second reading. Dust or
dirt in the gauge could cause the first reading to be
incorrect. Recommended tire pressure:
Fro nt27.5 kPa (0.275 kgf/cm ², 4.0 psi)
Rear 30.0 kPa (0.300 kgf/cm ², 4.4 psi)
Minimum tire pressure: Fro nt24.5 kPa (0.245 kgf/cm ², 3.6 psi)
Rear 27.0 kPa (0.270 kgf/cm ², 4.0 psi)
Maximum tire seating pressure: Fro nt250 kPa (2.5 kgf/cm ², 36 psi)
Rear 250 kPa (2.5 kgf/cm ², 36 psi)
U18P66E0.book Page 5 Monday, May 16, 2011 4:23 PM

5-6
5
Tire wear limit
When the tire groove decreases to 3 mm (0.12 in)
due to wear, replace the tire. Tire information
This ATV is equipped with tubeless tires with
valves.
WARNING
EWB02551Use of improper tires on this ATV may cause
loss of control, increasing your risk of an acci-
dent.After extensive tests, only the tires listed below
have been approved for this model by Yamaha
Motor Co., Ltd.
1. Low-pressure tire gauge
1
1. Tire wear limit
U18P66E0.book Page 6 Monday, May 16, 2011 4:23 PM

5-7
5Aftermarket tires and rims
The tires and rims that came with your ATV were
designed to match the performance capabilities
and to provide the best combination of handling,
braking, and comfort. Other tires, rims, sizes, and
combinations may not be appropriate.
EBU19840Chassis fasteners Make sure that all nuts, bolts and screws are prop-
erly tightened.
EBU19850Instruments, lights and switches Check that all instruments, lights and switches are
working properly. Correct if necessary.
Front:
Manufacturer/model:DUNLOP/KT352 Radial
Size: AT21 x 7R10
Ty p e : Tu b e l e s s
Rear: Manufacturer/model:DUNLOP/KT357 Radial
Size: AT 2 0 x 1 0 R 9
Ty p e : Tu b e l e s s
U18P66E0.book Page 7 Monday, May 16, 2011 4:23 PM

6-1
6
EBU19881
OPERATION
EBU19901Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00631Read 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.EBU29952Starting the engine NOTICEECB00150See the “Engine break-in ” section on page 6-4
prior to operating the engine for the first time.1. Set the parking brake.
2. Turn the key to “” (on) and the engine stop
switch to “”.
The following warning lights should come on
for a few seconds, then go off.

Coolant temperature warning light
Fuel level warning light
Engine trouble warning light
NOTICEECB00824If a warning light does not go off, see page 4-2
for the corresponding warning light circuit
check. To avoid possible damage, do not oper-
ate the ATV if a warning light stays on.3. Shift the transmission into neutral. The neutral indicator light should come on, if it does not
come on, have a Yamaha dealer check the
electrical circuit.TIPThis 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.
U18P66E0.book Page 1 Monday, May 16, 2011 4:23 PM

6-2
64. Completely close the throttle lever and start
the engine by pushing the start switch.
TIPIf the engine fails to start, release the start switch,
then push it again. Pause a few seconds before
the next attempt. Each cranking should be as short
as possible to preserve battery energy. Do not
crank the engine more than 10 seconds on each
attempt.NOTICEECB00163For maximum engine life, never accelerate
hard when the engine is cold!EBU20522Shifting This ATV has a 5-speed forward transmission. The
transmission allows you to control the amount of
power you have available at a given speed or for
starting, accelerating, climbing hills, etc.
To shift into neutral, release the throttle lever, ap-
ply the clutch, and then repeatedly depress the
shift pedal until it stops. When it stops, it will be in first gear. Raise the pedal
slightly to reach the neutral position, and then re-
lease the clutch.
EBU20592To start out and accelerate
1. Release the throttle lever, apply the front or rear brake, and then release the parking
brake.1. Shift pedal
2. Neutral position
1
2 2 3
4 5
N1
U18P66E0.book Page 2 Monday, May 16, 2011 4:23 PM

6-3
6
NOTICEECB00200Always 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, and then release thebrake.
4. Open the throttle gradually and at the same time, release the clutch lever slowly.
WARNING! Opening the throttle abruptly or releasing the clutch lever too quickly
could make the ATV wheelie, which would
increase the chance of an accident, includ-
ing an overturn.
[EWB00731]
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.
EBU20650To 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
EWB00710Make 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.NOTICEECB00180
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-
U18P66E0.book Page 3 Monday, May 16, 2011 4:23 PM

6-4
6erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage
the transmission.

Always use the clutch when changing gears.
The engine, transmission and drive train are
not designed to withstand the shock of
forced shifting and can be damaged by shift-
ing without using the clutch.EBU20672Engine break-in TIP
For ATVs equipped with an odometer or an hour
meter, follow the figures given in km (mi) or the
figures given in hours.
For ATVs not equipped with an odometer or
hour meter, follow the figures given in hours.There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 20
hours. The various parts in the engine wear and
polish themselves to the correct operating clear- ances. During this period, prolonged full-throttle
operation or any condition that might result in en-
gine overheating must be avoided.
0
–160 km (0 –100 mi) or 0 –10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160 –320 km (100 –200 mi) or 10 –20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine through the gears freely, but do not use
full throttle at any time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00220If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.EBU26761Parking When parking the ATV, shift into first gear, stop the
engine, and then apply the parking brake.
U18P66E0.book Page 4 Monday, May 16, 2011 4:23 PM