2013 YAMAHA YFZ450R Owners Manual

8-25
8
6. Remove the wing bolt and washer from the air
filter element.
7. Remove the sponge material from the air filter element frame. 8. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01941]
9. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do not twist
the sponge material when squeezing it.
[ECB00441]
1. Air filter element
2. Washer
3. Wing bolt
3
2
1
1. Sponge material
2. Air filter element frame
1
2
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8-26
810. Check the sponge material and replace it if
damaged.
11. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the sponge material.
TIPThe sponge material should be wet but not drip-
ping.12. Pull the sponge material over the air filter ele-ment frame.
13. Apply all-purpose grease to the air filter ele- ment seat. 14. Install the washer onto the air filter element
frame, and then insert the wing bolt into the
hole in the air filter element frame. NOTICE:
Be sure to install the washer with its
curved side facing outward as shown.
[ECB00453]
1. Air filter element seat
1
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8-27
8
15. Insert the air filter element into the air filter
case, and then tighten the wing bolt. NOTICE:
Make sure that the air filter element is
properly seated in the air filter case. Never
operate the engine with the air filter ele-
ment removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addi-
tionally, operation without the air filter ele-
ment will affect the fuel injection system
with subsequent poor performance and
possible engine overheating.
[ECB00761]
16. Install the air filter case cover by hooking the holders onto the air filter case. 17. Install the seat.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions. Check the air filter case rubber
joint to the throttle body and the rubber joint mani-
fold fittings for an air-tight seal. Tighten all fittings
securely to avoid the possibility of unfiltered air en-
tering the engine.EBU27703Cleaning the spark arrester Select a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe bolt.
1. Washer
1
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8-28
82. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing. 4. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install the bolt and tighten it to the specified torque.
6. Remove the purging bolt and the gasket.
1. Tailpipe bolt
2. Tailpipe
1
2
1. Tailpipe
2. Spark arresterTightening torque: Tailpipe bolt:8 Nm (0.8 m·kgf, 5.8 ft·lbf)
1
2
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8-29
8
7. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
8. Stop the engine and allow the exhaust pipe to cool.
9. Check the gasket for damage, and replace it if necessary.
10. Install the gasket and the purging bolt, and then tighten the bolt to the specified torque.
WARNING
EWB02380Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.●Always let the exhaust system cool prior to
touching exhaust components.●Always wear eye protection, and make sure
no one is behind the ATV.●Make sure there are no combustible materi-
als in the area.EBU29702Adjusting the throttle lever free play The throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
1. Purging bolt
2. Gasket
2
1
Tightening torque: Purging bolt:27 Nm (2.7 m·kgf, 20 ft·lbf)
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8-30
8The throttle lever free play should measure 2.0–
4.0 mm (0.08–0.16 in) as shown. Periodically
check the throttle lever free play and, if necessary,
adjust it as follows.
1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut. 5. Slide the rubber cover to its original position.
EBU24060Valve clearance The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.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 a
nd 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.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
32
4
(a)(b)
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8-31
8
EBU29560Front 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.TIPThe wheels need to be removed to check the
brake pads. (See page 8-50.)
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
1
1. Wear indicator groove
1
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8
EBU29501Checking the brake fluid level Before riding, check that the brake fluid is above
the minimum level mark. Check the brake fluid lev-
el with the top of the reservoir level. Replenish the
brake fluid if necessary.
Front brakeRear brake
TIPTo check the rear brake fluid level, remove the
seat. (See page 4-10.)
WARNING
EWB02720Improper maintenance can result in loss of
braking ability. Observe these precautions:
1. Minimum level mark
1
1. Minimum level markSpecified brake fluid:
DOT 4
1
U18P67E0.book Page 32 Wednesday, May 9, 2012 3:30 PM