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8 4. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag.
5. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.
NOTE:The engine oil should be between the minimumand maximum level marks.
6. 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.
7. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
8. Install the panel.
1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
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8
Make sure that no foreign material enters thecrankcase.
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, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
15. Install panel D.EBU23381Final 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.NOTE:The final gear oil level must be checked on a coldengine.2. Remove the final gear oil filler bolt, and then
check the oil level in the final gear case.
NOTE: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. Install the oil filler bolt, and then tighten it to the
specified torque.1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil level
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8
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.EBU24290Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the NOTE after the peri-
odic maintenance and lubrication chart. In addi-
tion, have the oil seals of the master cylinders 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.
EBU24390Checking 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 a
free play of zero mm (zero in) as shown. If the free
play is incorrect, have a Yamaha dealer check the
brake system.
WARNING
EWB02070Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:1. Brake lever free play
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EBU25222Battery This model is equipped with a sealed-type (MF)
battery, which does not require any maintenance.
There is no need to check the electrolyte or to add
distilled water. Check and, if necessary, tighten the
battery lead connections.CAUTION:ECB00620Never attempt to remove the battery cell seals,as this would permanently damage the battery.
WARNING
EWB02160Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause severe burns. Avoid contact with skin,
eyes or clothing. Always shield your eyes
when working near batteries.
Antidote:
EXTERNAL: Flush with water.INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of ig-
nition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN.
To charge the battery
Have a Yamaha dealer charge the battery as soon
as possible if it seems to have discharged. Keep in
mind that the battery tends to discharge more
quickly if the ATV is equipped with optional electri-
cal accessories.
To store the battery
1. If the ATV will not be used for more than one
month, remove the battery, fully charge it, and
then place it in a cool, dry place.
2. If the battery will be stored for more than two
months, check it at least once a month and ful-
ly charge it if necessary. Recommended lubricant:
Lithium-soap-based grease (all-purpose
grease)
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10-1
10
EBU25960
SPECIFICATIONS
Dimensions:Overall length:
1978 mm (77.9 in)
Overall width:
1063 mm (41.9 in)
Overall height:
1095 mm (43.1 in)
Seat height:
840 mm (33.1 in)
Wheelbase:
1233 mm (48.5 in)
Ground clearance:
220 mm (8.7 in)
Minimum turning radius:
3000 mm (118 in)Weight:With oil and fuel:
250.0 kg (551 lb)Engine:Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
421.0 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)Compression ratio:
10.00 :1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:Type:
SAE5W30 or SAE10W30 or SAE10W40 or SAE15W40
or SAE20W40 or SAE20W50
Recommended engine oil grade:
API service SG type or higher, JASO standard MA-20˚ -10˚ 0˚
10˚20˚ 30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
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Engine oil quantity:
Without oil filter cartridge replacement:
2.30 L (2.43 US qt) (2.02 Imp.qt)
With oil filter cartridge replacement:
2.40 L (2.54 US qt) (2.11 Imp.qt)Final gear oil:Type:
SAE80 API GL-4 Hypoid gear oil
Quantity:
0.23 L (0.24 US qt) (0.20 Imp.qt)Differential gear oil:Type:
SAE80 API GL-4 Hypoid gear oil
Quantity:
0.35 L (0.37 US qt) (0.31 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):
1.32 L (1.40 US qt) (1.16 Imp.qt)Air filter:Air filter element:
Wet elementFuel:Recommended fuel:
Regular unleaded gasoline only
Fuel tank capacity:
14.5 L (3.83 US gal) (3.19 Imp.gal)
Fuel reserve amount:
4.5 L (1.19 US gal) (0.99 Imp.gal)
Carburetor:Manufacturer:
MIKUNI
Type x quantity:
BSR33 x 1Spark plug (s):Manufacturer/model:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, centrifugal automaticTransmission:Primary reduction system:
V-belt
Secondary reduction system:
Shaft drive
Secondary reduction ratio:
39/24 × 24/18 × 33/9 (7.944)
Transmission type:
V-belt automatic
Operation:
Left hand operation
Forward gear:
38/23 (1.652)
Reverse gear:
29/17 (1.706)Chassis:Frame type:
Steel tube frame
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10
Front suspension:Type:
Double wishbone
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
160 mm (6.3 in)Rear suspension:Type:
Swingarm
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
180 mm (7.1 in)Electrical system:Ignition system:
DC. CDI
Charging system:
AC magnetoBattery:Model:
YTX20L-BS
Voltage, capacity:
12 V, 18.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage x quantity:Headlight:
12 V, 30.0/30.0 W × 2Tail/brake light:
12 V, 5.0/21.0 W × 1
Neutral indicator light:
LED
Reverse indicator light:
LED
Coolant temperature warning light:
LED
Park indicator light:
LED
On-Command four-wheel-drive indicator:
LCD
Fuses:Main fuse:
30.0 A
Headlight fuse:
15.0 A
Signaling system fuse:
10.0 A
Ignition fuse:
10.0 A
Auxiliary DC jack fuse:
10.0 A
Backup fuse:
10.0 A
Four-wheel-drive motor fuse:
3.0 A
U3C262E0.book Page 4 Tuesday, June 26, 2007 3:36 PM