2012 YAMAHA YFZ450R fuel

8-13
8
4. 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. Tighten the quick fasteners.
4. Install the fuel tank cap by turning it clockwise.
5. Install the seat.
1. Quick fastener
1. Quick fastener
1 1
1
1. Projection
2. Slot
11
2
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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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8-30
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 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
32
4
(a)(b)
1U18P66E0.book Page 30 Monday, May 16, 2011 4:23 PM

8-52
8
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.U18P66E0.book Page 52 Monday, May 16, 2011 4:23 PM

8-53
8
EBU27693Troubleshooting 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.
Check the battery.
DryWet
Operate the electric starter.
The engine does not start.
Have a Yamaha dealer
check the ATV.
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 have a Yamaha dealer charge
the battery if necessary.
U18P66E0.book Page 53 Monday, May 16, 2011 4:23 PM

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9
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)U18P66E0.book Page 2 Monday, May 16, 2011 4:23 PM

10-1
10
EBU25961
SPECIFICATIONS
Dimensions:Overall length:1795 mm (70.7 in)
Overall width: 1240 mm (48.8 in)
Overall height:
1065 mm (41.9 in)
Seat height: 810 mm (31.9 in)
Wheelbase: 1270 mm (50.0 in)
Ground clearance:
235 mm (9.3 in)
Minimum turning radius: 3600 mm (142 in)Weight:With oil and fuel:
184.0 kg (406 lb)Noise and vibration level:Noise level (77/311/EEC):YFZ450RB 85.9 dB(A)@3750 r/min (EUR)(FRA)(GBR)
YFZ450RSEB 85.9 dB(A)@3750 r/min
(EUR)(FRA)(GBR)
A-weighted sound power level: YFZ450RB 99.0 dB(A)@3750 r/min (EUR)(FRA)(GBR)
YFZ450RSEB 99.0 dB(A)@3750 r/min
(EUR)(FRA)(GBR) Vibration on seat (EN1032, ISO5008):
YFZ450RB Will not exceed 0.5 m/s ² (EUR)(FRA)(GBR)
YFZ450RSEB Will not exceed 0.5 m/s ²
(EUR)(FRA)(GBR)
Vibration on handlebar (EN1032, ISO5008): YFZ450RB Will not exceed 2.5 m/s ² (EUR)(FRA)(GBR)
YFZ450RSEB Will not exceed 2.5 m/s ²
(EUR)(FRA)(GBR)
Engine:Engine type: Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement: 449 cm ³
Bore × stroke:
95.0 × 63.4 mm (3.74 × 2.50 in)
Compression ratio:
11.40 : 1
Starting system: Electric starter
Lubrication system: Dry sumpEngine oil:Recommended brand:YAMALUBE
U18P66E0.book Page 1 Monday, May 16, 2011 4:23 PM

10-2
10
Type:SAE 5W-30, 10W-30, 10W-40, 15W-40, 20W-40 or 20W-
50
Recommended engine oil grade: API service SG type or higher, JASO standard MA
Engine oil quantity: Without oil filter element replacement:
1.40 L (1.48 US qt, 1.23 Imp.qt)
With oil filter element replacement: 1.45 L (1.53 US qt, 1.28 Imp.qt)Cooling system:Coolant reservoir capacity (up to the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator capacity (including all routes): 1.25 L (1.32 US qt, 1.10 Imp.qt)
Air filter:Air filter element:Wet elementFuel:Recommended fuel:Premium unleaded gasoline only
Fuel tank capacity: 10.0 L (2.64 US gal, 2.20 Imp.gal)
Fuel reserve amount:
3.4 L (0.90 US gal, 0.75 Imp.gal)Fuel injection:Throttle body:ID mark:18P1 00Spark plug (s):Manufacturer/model:
NGK/CR8E
Spark plug gap: 0.7 –0.8 mm (0.028 –0.031 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction system:Spur gear
Primary reduction ratio:
61/23 (2.652)
Secondary reduction system: Chain drive
Secondary reduction ratio: 38/14 (2.714)
0 10 30 50 70 90 110 130 ˚F
–20 –10 0 10 20 30 40 50 ˚CSAE 5W-30
SAE 10W-30
SAE 10W-40
SAE 15W-40
SAE 20W-40SAE 20W-50
U18P66E0.book Page 2 Monday, May 16, 2011 4:23 PM