2012 YAMAHA YFZ450 service

4-17
48. Place the air filter case in the original position,
connect the air intake duct, and then tighten
the clamp screw at the carburetor side.
NOTICE: Make sure that the air intake duct
is properly connected to the carburetor,
and that the clamp screw is tightened se-
curely.
[ECB01170]
9. Install the bolts, install the hose joint, and then connect the hoses.
10. Install the seat.
WARNING
EWB00450This shock absorber assembly contains highly
pressurized nitrogen gas. If the shock absorb-
er assembly is damaged, it could explode
causing injury or property damage. Shock ab-
sorber cylinder damage could also result in
poor handling which could cause an accident.
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.

Do not deform or damage the cylinder in any
way.
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.
Tightening torque: Locknut:44 Nm (4.4 m ·kgf, 32 ft· lbf)
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8-1
8
EBU28783
PERIODIC MAINTENANCE AND ADJUSTMENT
EBU21674Periodic inspection, adjustment, and lubrication
will keep your vehicle in the safest and most effi-
cient condition possible. Safety is an obligation of
the vehicle owner/operator. The most important
points of vehicle inspection, adjustment, and lubri-
cation are explained on the following pages.
WARNING
EWB01841Failure to properly maintain the vehicle or per-
forming maintenance activities incorrectly may
increase your risk of injury or death during ser-
vice or while using the vehicle. If you are not fa-
miliar with vehicle service, have a Yamaha
dealer perform the service.
WARNING
EWB02562Turn off the engine when performing mainte-
nance unless otherwise specified.
A running engine has moving parts that can
catch on body parts or clothing and electri-
cal parts that can cause shocks or fires.

Running the engine while servicing can lead
to eye injury, burns, fire, or carbon monoxide
poisoning - possibly leading to death. See
page 2-3 for more information about carbon
monoxide.
WARNING
EWB02690Brake discs, calipers, drums, and linings can
become very hot during use. To avoid possible
burns, let brake components cool before
touching them.The intervals given in the periodic maintenance
charts should be considered as a general guide
under normal riding conditions. However, DE-
PENDING ON THE WEATHER, TERRAIN, GEO-
GRAPHICAL LOCATION, AND INDIVIDUAL
USE, THE MAINTENANCE INTERVALS MAY
NEED TO BE SHORTENED.
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8-2
8
EBU27111Owner’s manual and tool kit Be sure to put this owner ’s manual in the plastic
bag and to always carry it as well as the owner ’s
tool kit and the low-pressure tire gauge in their re-
spective compartments under the seat.
The service information included in this manual
and the tools provided in the owner ’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However, additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIPIf you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.
1. Low-pressure tire gauge
2. Owner
’s tool kit
3. Owner ’s manual
3
2
1
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8-8
8
EBU23071TIP
Some maintenance items need more frequent service if you are riding in unusually wet, dusty, sandy or
muddy areas, or at full-throttle.
Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
 Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.
 Replace the brake hoses every four years and if cracked or damaged.23 *Moving parts and
cables 
Lubricate. √√√√
24 *Throttle lever 
Check operation.
 Check throttle lever free play, and adjust if neces-
sary.
 Lubricate cable and lever housing. √√√√√
25 *Front and rear brake
switches 
Check operation and correct if necessary. √√√√√
26 *Lights and switches 
Check operation and correct if necessary.
 Adjust headlight beams. √√√√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320U1PD60E0.book Page 8 Monday, June 13, 2011 2:57 PM

8-32
8
EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU24130Checking the front and rear brake pads The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart.EBU27711Front brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves are almost in con-
tact with the disc plate, have a Yamaha dealer re-
place the brake pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 8-54.)EBU29831Rear brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost disap-
peared, have a Yamaha dealer replace the brake
pads as a set.1. Wear indicator groove
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8-38
8
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
8. Turn in the adjusting bolt at the rear brake cal-iper until it feels tight, then turn it out 1/8 turn
and tighten its locknut to the specified torque.
NOTICE: When tightening the locknut, hold the adjusting bolt with a wrench so
that it does not turn together with the lock-
nut.
[ECB00521]
WARNING
EWB02090Operating with improperly serviced or adjust-
ed brakes could cause the brakes to malfunc-
tion, resulting in reduced braking
performance. This could increase the chance
of a collision or accident. After adjusting the
parking brake free play, block the rear of the
ATV off the ground and spin the rear wheels.
Check to make sure there is no brake drag. If
brake drag is noticed, perform the adjustment
again.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
(a)
(b)
1
2
3
Tightening torque: Locknut (rear brake caliper):16 Nm (1.6 m ·kgf, 12 ft· lbf)
U1PD60E0.book Page 38 Monday, June 13, 2011 2:57 PM

8-43
8
EBU24882Lubricating the drive chain The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.NOTICEECB00561The drive chain must be lubricated after wash-
ing the ATV or riding in the rain or wet areas.1. Clean the drive chain with kerosene and asmall soft brush. NOTICE: To prevent dam-
aging the O-rings, do not clean the drive
chain with steam cleaners, high-pressure
washers or inappropriate solvents.
[ECB00571]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a special O-ring chain lubricant. NOTICE: Do
not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00581]
EBU24902
Checking and lubricating the cables The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-1. O-rings
1
1
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8-56
8The following troubleshooting charts represent
quick and easy procedures for checking these vital
systems yourself. However, should your ATV re-
quire any repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary tools, expe-
rience, and know-how to service the ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWB02280Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces.U1PD60E0.book Page 56 Monday, June 13, 2011 2:57 PM