fuel YAMAHA YFZ450R 2011 User Guide

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.EBU29951Starting 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“” 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.
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8
EBU21743Periodic maintenance chart for the emission control system TIP
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills.NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
Replace. Every 5 years
2*Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
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8
EBU29430TIP
Some maintenance items need more frequent service if you are riding in unusually wet, dusty, sandy or
muddy areas, or at full-throttle.
Replace the fuel hose every five years and if cracked or damaged.
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*Throttle lever hous-
ing and cableCheck operation and correct if necessary.
Check throttle lever free play and adjust if neces-
sary.
Lubricate throttle lever housing and cable.√√√√√
24*Front and rear brake
switchesCheck operation and correct if necessary.√√√√√
25*Lights and switchesCheck operation and correct if necessary.
Adjust headlight beams.√√√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320U18P64E0.book Page 8 Thursday, May 13, 2010 6:00 PM

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8
EBU30130Removing and installing the cowling
and panels The cowling and panels shown need to be re-
moved to perform some of the maintenance jobs
described in this chapter. Refer to this section each
time a cowling or panel needs to be removed and
installed.
EBU29536Panel A
To remove the panel1. Remove the seat. (See page 4-10.)
2. Remove the fuel tank cap by turning it coun-
terclockwise. (See page 4-8.) NOTICE: Make
sure that no foreign material enters the
fuel tank.
[ECB01051]
3. Remove the bolts.
1. Panel A
2. Panel B
3. Cowling
1
2
3
1. Panel C
1
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84. Remove the quick fasteners, and then slide
the panel backward and pull upward.5. Install the fuel tank cap by turning it clockwise.
To install the panel
1. Remove the fuel tank cap by turning it coun-
terclockwise.
2. Place the panel in the original position, and
then install the quick fasteners. NOTICE:
When installing the panel, be sure not to
pinch the cables or wires.
[ECB00381]
3. Install the bolts.
4. Install the fuel tank cap by turning it clockwise.
5. Install the seat.
1. Bolt
1. Quick fastener
1
1
1
1. Projection
2. Slot
11
2
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815. 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.EBU27702Cleaning the spark arrester Select a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the bolt.
1. Washer
1
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8 The throttle lever free play should measure 2.0–
4.0 mm (0.08–0.16 in) at the throttle lever. Period-
ically check the throttle lever free play and, if nec-
essary, 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 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.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
3 2
4 (a)(b)
1
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8 3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified
torques.
EBU25740Troubleshooting Although Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the fu-
el, compression, or ignition systems, for example,
can cause poor starting and loss of power.
The 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.
Tightening torques:
Front wheel nut:
45 Nm (4.5 m·kgf, 33 ft·lbf)
Rear wheel nut:
45 Nm (4.5 m·kgf, 33 ft·lbf)
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EBU27691Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the ATV.
The engine does not start.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Operate the electric starter.
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EBU27261Storage Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00721]
Long-term
Before storing your ATV for several months:
1. Follow all the instructions in the “Cleaning”
section of this chapter.
2. Fill up the fuel tank and add fuel stabilizer (if
available) to prevent the fuel from deteriorat-
ing.3. Perform the following steps to protect the cyl-
inder, piston rings, etc. from corrosion.
a. Remove the spark plug cap and spark
plug.
b. Pour a teaspoonful of engine oil into the
spark plug bore.
c. Install the spark plug cap onto the spark
plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the
starter. (This will coat the cylinder wall with
oil.)
e. Remove the spark plug cap from the spark
plug, and then install the spark plug and
the spark plug cap.
4. Lubricate all control cables and the pivoting
points of all levers and pedals.
5. Check and, if necessary, correct the tire air
pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
ly, turn the wheels a little every month in order
to prevent the tires from becoming degraded
in one spot. Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U18P64E0.book Page 2 Thursday, May 13, 2010 6:00 PM