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8-18
8
TIPWhen adding oil, be careful not to overfill the en-
gine oil tank; the oil level rises faster starting from
the half-level mark on the dipstick.6. Insert the dipstick into the engine oil tank fillerhole, and then tighten the engine oil tank filler
cap. NOTICE: Make sure that the engine oil
tank filler cap is securely tightened; other-
wise, oil may seep out when the engine is
running.
[ECB00362]
To change the engine oil (with or without oil fil-
ter element replacement) 1. Place the ATV on a level surface.
2. Remove the engine guard by removing the bolts. 3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect the used oil.
5. Remove the engine oil tank filler cap, and then remove the engine oil tank drain bolt and its
gasket.
1. Engine guard
2. Bolt
2 21
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8-19
8
6. Remove the crankcase engine oil drain bolt
and its gasket.
TIPSkip steps 7 –10 if the oil filter element is not being
replaced.7. Remove the oil filter element cover by remov- ing the bolts.
1. Engine oil tank drain bolt
2. Gasket
1
2
1. Crankcase engine oil drain bolt
2. Gasket
12
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8-21
8
11. Install the crankcase engine oil drain bolt, the
engine oil tank drain bolt and their new gasket,
and then tighten the bolts to their specified
torques.
12. Refill with the specified amount of the recom- mended engine oil through the engine oil tank
filler hole, and then install and tighten the en-
gine oil tank filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.NOTICEECB00300In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD ” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II ” or higher.Make sure that no foreign material enters the
crankcase.13. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
14. Turn the engine off, and then check the oil lev- el and correct it if necessary.
Tightening torques:
Crankcase engine oil drain bolt:20 Nm (2.0 m ·kgf, 14 ft ·lbf)
Engine oil tank drain bolt: 20 Nm (2.0 m ·kgf, 14 ft ·lbf)
Recommended oil: See page 10-1.
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)
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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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8-41
8
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02581Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could
restrict the operation of controls and lead to
an accident or injury.Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-
dent or collision.
EBU24922Checking and lubricating the brake and
clutch levers The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Brake lever
Recommended lubricant:
Yamaha Chain and Cable Lube or engine oilRecommended lubricants: Brake lever:Silicone grease
Clutch lever: Lithium-soap-based grease
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9-2
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
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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
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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
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