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8-12
8
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
NOTICE: Be sure the engine oil is at the
correct level, otherwise engine damage
may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.To change the engine oil (with or without oil fil-
ter element cleaning)
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00311]
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level markU1P066E0.book Page 12 Thursday, August 5, 2010 4:15 PM
Page 97 of 140

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8
EBU23386Final gear oil The final gear case must be checked for oil leak-
age before each ride. If any leakage is found, have
a Yamaha dealer check and repair the ATV. In ad-
dition, the final gear oil level must be checked and
the oil changed as follows at the intervals specified
in the periodic maintenance and lubrication chart.
To check the final gear oil level
1. Place the ATV on a level surface.
2. Remove the final gear oil filler bolt and its gas-
ket, and then check the oil level in the final
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.
5. Install the oil filler bolt and its gasket, and then
tighten the bolt to the specified torque.
1. Final gear oil filler bolt
2. Gasket
3. Final gear oil
4. Correct oil levelTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1
2
4
3
U1P066E0.book Page 18 Thursday, August 5, 2010 4:15 PM
Page 109 of 140

8-30
8
Use only the recommended quality brake fluid,
otherwise the rubber seals may deteriorate,
causing leakage and poor braking performance.Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.EBU24281Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,have the oil seals of the brake master cylinder and
calipers as well as the brake hoses replaced at the
intervals listed below or whenever they are dam-
aged or leaking.
Oil seals: Replace every two years.Brake hoses: Replace every four years.EBU24394Checking the front brake lever free play The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system. Recommended brake fluid:
DOT 41. No brake lever free play
U1P066E0.book Page 30 Thursday, August 5, 2010 4:15 PM
Page 132 of 140
10-1
10
EBU25960
SPECIFICATIONS
Dimensions:Overall length:
1916 mm (75.4 in)
Overall width:
1038 mm (40.9 in)
Overall height:
1118 mm (44.0 in)
Seat height:
772 mm (30.4 in)
Wheelbase:
1170 mm (46.1 in)
Ground clearance:
150 mm (5.9 in)
Minimum turning radius:
2900 mm (114 in)Weight:With oil and fuel:
216.0 kg (476 lb)Noise and vibration level:Noise level (77/311/EEC):
YFM25BA 77.5 dB(A)
Vibration on seat (EN1032, ISO5008):
YFM25BA Will not exceed 0.5 m/s²
Vibration on handlebar (EN1032, ISO5008):
YFM25BA Will not exceed 2.5 m/s²Engine:Engine type:
Air cooled 4-stroke, SOHCCylinder arrangement:
Forward-inclined single cylinder
Displacement:
229 cm³
Bore × stroke:
71.0 × 58.0 mm (2.80 × 2.28 in)
Compression ratio:
8.70 :1
Starting system:
Electric and recoil starter
Lubrication system:
Wet sump
Engine oil:Recommended brand:
YAMALUBE
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Page 133 of 140

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 removal:
1.50 L (1.59 US qt, 1.32 Imp.qt)
With oil filter element removal:
1.60 L (1.69 US qt, 1.41 Imp.qt)Final gear oil:Type:
SAE 80 API GL-4 Hypoid gear oil
Quantity:
0.25 L (0.26 US qt, 0.22 Imp.qt)
Air filter:Air filter element:
Dry elementFuel:Recommended fuel:
YFM250A Unleaded gasoline only
YFM25BA Regular unleaded gasoline only
Fuel tank capacity:
12.0 L (3.17 US gal, 2.64 Imp.gal)
Fuel reserve amount:
1.6 L (0.42 US gal, 0.35 Imp.gal)Carburetor:Type × quantity:
BSR33 x 1Spark plug (s):Manufacturer/model:
NGK/DR7EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, centrifugal automaticTransmission:Primary reduction system:
Spur gear
Primary reduction ratio:
73/22 (3.318)
Secondary reduction system:
Shaft drive
Secondary reduction ratio:
19/18 × 46/11 (4.414)
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
U1P066E0.book Page 2 Thursday, August 5, 2010 4:15 PM
Page 135 of 140
10-4
10
Rim size:
10 x 8.0ATFront brake:Type:
Disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4Rear brake:Type:
Drum brake
Operation:
Left hand and right foot operationFront suspension:Type:
Strut
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
125 mm (5.0 in)Rear suspension:Type:
Swingarm (monocross)
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
135 mm (5.3 in)Electrical system:Ignition system:
DC CDICharging system:
AC magneto
Battery:Model:
CB14A-A2
Voltage, capacity:
12 V, 14.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage × quantity:Headlight:
12 V, 30.0/30.0 W × 2
Tail/brake light:
12 V, 5.0/21.0 W × 1
Neutral indicator light:
12 V, 1.7 W × 1
Reverse indicator light:
12 V, 1.7 W × 1Fuse:Fuse:
20.0 A
U1P066E0.book Page 4 Thursday, August 5, 2010 4:15 PM