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8-20
8
TIPIf the engine was started before checking the oil
level, warm up the engine, and then wait at least
ten minutes until the oil settles for an accurate
reading. 4. Remove the engine oil filler cap, and thenwipe the dipstick 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.
TIPThe engine oil should be between the tip of the
dipstick and the maximum level mark. 6. If the engine oil is not between the tip of thedipstick and the maximum level mark, add
sufficient oil of the recommended type to
raise it to the correct level. NOTICE: Be sure
the engine oil is at the correct level, other-
wise engine damage may result.
[ECB00852]
1. Engine oil filler cap
1
1. Engine oil filler cap
2. O-ring
3. Engine oil dipstick
4. Maximum level mark
5. Tip of the engine oil dipstick
12345
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8-24
8
13. Check the engine oil filler cap O-ring for dam-
age, and then install the filler cap.
14. Start the engine and let it idle for several min- utes while checking for oil leakage. If any oil
leakage is found, immediately turn the engine
off and check for the cause.
15. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
16. Install panel E.
EBU28568Final gear oilThe 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 speci-
fied in the periodic maintenance and lubrication
chart.
To check the final gear oil level 1. Park 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 oil filler bolt 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:22 N·m (2.2 kgf·m, 16 lb·ft)1
2
3
4
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Page 157 of 166
10-2
10
Cooling system:Liquid cooled
Valve train: SOHC
Number of cylinders:
Single cylinder
Displacement: 421 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)
Compression ratio:
10.0 : 1
Starting system: Electric starter
Lubrication system: Wet sumpEngine oil:Recommended brand:YAMALUBE
SAE viscosity grades: 5W-30, 10W-30, 10W-40, 15W-40, 20W-40, 20W-50 Recommended engine oil grade:
API service SG type or higher, JASO standard MA
Quantity: Oil change:2.30 L (2.43 US qt, 2.02 Imp.qt)
With oil filter removal: 2.40 L (2.54 US qt, 2.11 Imp.qt)
Final gear oil:Type:Yamaha Friction Modified Shaft Drive Gear Oil
Quantity: 0.38 L (0.40 US qt, 0.33 Imp.qt)Differential gear oil:Type:Yamaha Friction Modified Shaft Drive Gear Oil or SAE 80
API GL-4 Hypoid gear oil
Quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)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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10-3
10
Coolant quantity:Radiator (including all routes):1.32 L (1.40 US qt, 1.16 Imp.qt)
Coolant reservoir (up to the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)Air filter:Air filter element:Wet element
Air filter oil grade:
Foam air-filter oilFuel:Recommended fuel:Regular unleaded gasoline (Gasohol [E10] acceptable)
Minimum research octane:
91
Fuel tank capacity: 14 L (3.7 US gal, 3.1 Imp.gal)
Fuel reserve amount: 4.0 L (1.06 US gal, 0.88 Imp.gal)Throttle body:ID mark:BB51 00Spark plug (s):Manufacturer/model:
NGK/DR7EA
Spark plug gap: 0.6–0.7 mm (0.024–0.028 in)Drivetrain:Primary reduction ratio:
1.000 Secondary reduction ratio:
7.944 (39/24 x 24/18 x 33/9)
Final drive: Shaft
Clutch type:
Wet, centrifugal, shoe
Transmission type: CVT automatic with reverse
Gear ratio: Transmission ratio: 2.550–0.750 : 1
Reverse gear: 1.706 (29/17)
Low range:
2.813 (45/16)
High range: 1.652 (38/23)
Front tire:Size:
AT25 x 8-12
Manufacturer/model: CHENG SHIN/CU905Rear tire:Size:
AT25 x 10-12
Manufacturer/model: CHENG SHIN/CU906Tire air pressure (measured on cold tires):Recommended (For Oceania):
Front: 35.0 kPa (0.350 kgf/cm², 5.0 psi)
(YFM45KDXK_AUS/NZL, YFM45KPXK_AUS/NZL)
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10-4
10
Rear:30.0 kPa (0.300 kgf/cm², 4.4 psi)
(YFM45KDXK_AUS/NZL, YFM45KPXK_AUS/NZL)
Minimum (For Oceania): Front:
32.0 kPa (0.320 kgf/cm², 4.6 psi)
(YFM45KDXK_AUS/NZL, YFM45KPXK_AUS/NZL)
Rear:
27.0 kPa (0.270 kgf/cm², 3.9 psi)
(YFM45KDXK_AUS/NZL, YFM45KPXK_AUS/NZL)
No cargo or trailer (For Europe):
Front:35.0 kPa (0.350 kgf/cm², 5.0 psi) (YFM45KDHK,
YFM45KDXK_EUR/FRA/GBR, YFM45KPHK,
YFM45KPLK, YFM45KPXK_EUR/FRA/GBR)
Rear: 30.0 kPa (0.300 kgf/cm², 4.4 psi) (YFM45KDHK,
YFM45KDXK_EUR/FRA/GBR, YFM45KPHK,
YFM45KPLK, YFM45KPXK_EUR/FRA/GBR)
With cargo or trailer (For Europe):
Front:50.0 kPa (0.500 kgf/cm², 7.3 psi) (YFM45KDHK,
YFM45KDXK_EUR/FRA/GBR, YFM45KPHK,
YFM45KPLK, YFM45KPXK_EUR/FRA/GBR)
Rear: 50.0 kPa (0.500 kgf/cm², 7.3 psi) (YFM45KDHK,
YFM45KDXK_EUR/FRA/GBR, YFM45KPHK,
YFM45KPLK, YFM45KPXK_EUR/FRA/GBR)
Front wheel:Rim size:12 x 6.0AT
Rear wheel:Rim size:12 x 7.5ATFront brake:Type:Hydraulic disc brakeRear brake:Type:
Mechanical wet multiple disc brakeBrake fluid:Specified brake fluid:DOT 4Front suspension:Type:Double wishbone
Spring: Coil spring
Shock absorber:
Gas-hydraulic damper
Wheel travel: 171 mm (6.8 in)Rear suspension:Type:
Double wishbone
Spring: Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
189 mm (7.4 in)
UBB561E0.book Page 4 Monday, March 26, 2018 11:15 AM