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8-27
8
2. Remove the final gear oil level check bolt and
its gasket, and then check the oil level in the
final gear case. The oil level should be at the
brim of the check hole.
3. If the oil is below the brim of the check hole, remove the final gear oil filler bolt and its gas-
ket, and then add sufficient oil of the recom-
mended type to raise it to the correct level. 4. Check the gaskets for damage, and replace
them if necessary.
5. Install the oil level check bolt, the oil filler bolt and their gasket, and then tighten the bolts to
the specified torques.
1. Final gear oil
2. Gasket
3. Final gear oil level check bolt
4. Correct oil level
1
243
1. Final gear oil filler bolt
2. GasketTightening torques:Final gear oil level check bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Final gear oil filler bolt: 23 Nm (2.3 m·kgf, 17 ft·lbf)
1
2
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8-28
8To change the final gear oil
1. Place the ATV on a level surface.
2. Place an oil pan under the final gear case to collect the used oil.
3. Remove the final gear oil filler bolt, the final gear oil level check bolt, the final gear oil drain
bolt and their gasket to drain the oil from the
final gear case.
4. Install the drain bolt and its new gasket, and then tighten the bolt to the specified torque. 5. Refill with the recommended final gear oil to
the brim of the check hole as shown.
NOTICE: Be sure no foreign material en-
ters the final gear case.
[ECB00422]
1. Final gear oil drain bolt
2. Gasket
12
Tightening torque: Final gear oil drain bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)1. Final gear oil
2. Gasket
3. Final gear oil level check bolt
4. Correct oil levelRecommended final gear oil:See page 10-1.
1
243
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8-29
8
6. Check the oil level check bolt gasket and the
oil filler bolt gasket for damage, and replace
them if necessary.
7. Install the oil level check bolt, the oil filler bolt and their gasket, and then tighten the bolts to
the specified torques.
8. Check the final gear case for oil leakage. If oil is leaking, check for the cause.
EBU23427Differential gear oilThe differential gear case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the differential gear oil level must be
checked and the oil changed as follows at the in-
tervals specified in the periodic maintenance and
lubrication chart. To check the differential gear oil level
1. Place the ATV on a level surface.
2. Remove the differential gear oil filler bolt and its gasket, and then check the oil level in the
differential gear case. The oil level should be
at the brim of the filler hole.
3. If the oil is below the brim of the filler hole, add sufficient oil of the recommended type to
raise it to the correct level.
4. Check the gasket for damage, and replace it if necessary.
Tightening torques:
Final gear oil level check bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Final gear oil filler bolt: 23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Differential gear oil filler bolt
2. Gasket
3. Differential gear oil
4. Correct oil level
1
2
3
4
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8-30
85. Install the oil filler bolt and its gasket, and then
tighten the bolt to the specified torque.
To change the differential gear oil 1. Place the ATV on a level surface.
2. Place an oil pan under the differential gear case to collect the used oil.
3. Remove the differential gear oil filler bolt, the differential gear oil drain bolt and their gasket
to drain the oil from the differential gear case. 4. Install the drain bolt and its new gasket, and
then tighten the bolt to the specified torque.
5. Refill with the recommended differential gear oil to the brim of the filler hole as shown.
NOTICE: Be sure no foreign material en-
ters the differential gear case.
[ECB00412]
Tightening torque: Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)1. Differential gear oil drain bolt
2. Gasket
12
Tightening torque:Differential gear oil drain bolt:9.8 Nm (0.98 m·kgf, 7.1 ft·lbf)1. Differential gear oil filler bolt
2. Gasket
3. Differential gear oil
4. Correct oil level
1
2
3
4
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8-31
8
6. Check the oil filler bolt gasket for damage,
and replace it if necessary.
7. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
8. Check the differential gear case for oil leak- age. If oil is leaking, check for the cause.
EBU23471CoolantThe coolant level should be checked before each
ride. In addition, the coolant must be changed at
the intervals specified in the periodic maintenance
and lubrication chart.EBU27127To check the coolant level1. Place the ATV on a level surface.
TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture. 2. Check the coolant level in the coolant reser- voir.TIPThe coolant should be between the minimum and
maximum level marks.
Recommended differential gear oil:See page 10-1.
Tightening torque: Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Maximum level mark
2. Minimum level mark
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8-48
8Rear brake
WARNING
EWB02721Improper maintenance can result in loss of
braking ability. Observe these precautions:
Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
Be careful that water does not enter the
brake fluid reservoir when refilling. Water will
significantly lower the boiling point of the flu-
id and may result in vapor lock.
NOTICEECB01161Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately. As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads and/or brake
system leakage; therefore, be sure to check the
brake pads for wear and the brake system for
leakage. If the brake fluid level goes down sud-
denly, have a Yamaha dealer check the cause be-
fore further riding.
1. Minimum level markSpecified brake fluid:
DOT 4
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10-1
10
EBU25962
SPECIFICATIONS
Dimensions:Overall length:2065 mm (81.3 in)
Overall width: 1180 mm (46.5 in)
Overall height:
1240 mm (48.8 in)
Seat height: 905 mm (35.6 in)
Wheelbase: 1250 mm (49.2 in)
Ground clearance:
275 mm (10.8 in)
Minimum turning radius: 3200 mm (126 in)Weight:Curb weight:
294.0 kg (648 lb)Noise and vibration level:Noise level (77/311/EEC):YFM550DF 79.0 dB(A)@2950 r/min (EUR)(FRA)(GBR)
YFM550PF 79.0 dB(A)@2950 r/min (EUR)(FRA)(GBR)
YFM550PHF 79.0 dB(A)@2950 r/min
Vibration on seat (EN1032, ISO5008): YFM550DF Will not exceed 0.5 m/s² (EUR)(FRA)(GBR)
YFM550PF Will not exceed 0.5 m/s² (EUR)(FRA)(GBR)
YFM550PHF Will not exceed 0.5 m/s² Vibration on handle (EN1032, ISO5008):
YFM550DF Will not exceed 2.5 m/s² (EUR)(FRA)(GBR)
YFM550PF Will not exceed 2.5 m/s² (EUR)(FRA)(GBR)
YFM550PHF Will not exceed 2.5 m/s²
Engine:Engine type:Liquid cooled 4-stroke, SOHC
Cylinder arrangement: Single cylinder
Displacement: 558 cm³
Bore × stroke:
92.0 × 84.0 mm (3.62 × 3.31 in)
Compression ratio: 9.3 : 1
Starting system: Electric starter
Lubrication system:
Wet 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 cartridge replacement:2.00 L (2.11 US qt, 1.76 Imp.qt)
With oil filter cartridge replacement: 2.10 L (2.22 US qt, 1.85 Imp.qt)Final gear oil:Type:SAE 80 API GL-4 Hypoid gear oil
Quantity: 0.20 L (0.21 US qt, 0.18 Imp.qt)Differential gear oil:Type:SAE 80 API GL-4 Hypoid gear oil Quantity:
0.22 L (0.23 US qt, 0.19 Imp.qt)
Cooling system:Coolant reservoir capacity (up to the maximum level mark):
0.24 L (0.25 US qt, 0.21 Imp.qt)
Radiator capacity (including all routes): 1.99 L (2.10 US qt, 1.75 Imp.qt)Air filter:Air filter element:
Wet elementFuel:Recommended fuel:Regular unleaded gasoline only
Fuel tank capacity:
20.0 L (5.28 US gal, 4.40 Imp.gal)
Fuel reserve amount: 4.5 L (1.19 US gal, 0.99 Imp.gal)Fuel injection:Throttle body:
ID mark:28P7 10Spark plug (s):Manufacturer/model:NGK/LMAR6A-9
Spark plug gap: 0.8–0.9 mm (0.031–0.035 in)Clutch:Clutch type:Wet, centrifugal automatic
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
U2LB61E0.book Page 2 Friday, February 21, 2014 3:03 PM