2008 YAMAHA YFM50R air filter

RIDING YOUR ATV ...................................... 7-1
GETTING TO KNOW YOUR ATV.............. 7-2
RIDE WITH CARE AND GOOD
JUDGEMENT ........................................... 7-2
BE CAREFUL WHERE YOU RIDE ............ 7-9
TURNING YOUR ATV ............................. 7-12
CLIMBING UPHILL .................................. 7-14
RIDING DOWNHILL................................. 7-16
CROSSING A SLOPE.............................. 7-17
CROSSING THROUGH SHALLOW
WATER .................................................. 7-18
RIDING OVER ROUGH TERRAIN .......... 7-20
SLIDING AND SKIDDING ........................ 7-20
WHAT TO DO IF... ................................... 7-21
WHAT TO DO... ....................................... 7-21
PERIODIC MAINTENANCE AND MINOR
REPAIR .......................................................... 8-1
Owner’s manual and tool kit ...................... 8-1
Periodic maintenance chart for the
emission control system .......................... 8-3
General maintenance and lubrication
chart ........................................................ 8-5
Checking the spark plug ............................ 8-8
Engine oil .................................................. 8-9
Final gear oil ............................................ 8-12
Cleaning the air filter element ................. 8-13
Cleaning the spark arrester ..................... 8-17
Adjusting the carburetor .......................... 8-18Adjusting the engine idling speed ............ 8-18
Checking the throttle cable free play ....... 8-19
Valve clearance ....................................... 8-19
Checking the front and rear brake
shoes ..................................................... 8-20
Adjusting the front brake lever free play .. 8-21
Adjusting the rear brake lever free play ... 8-23
Checking and lubricating the cables ........ 8-24
Checking and lubricating the front and
rear brake levers .................................... 8-25
Checking the wheel hub bearings ............ 8-25
Lubricating the front knuckle pivots ......... 8-25
Lubricating the steering shaft ................... 8-26
Battery ..................................................... 8-26
Replacing the fuse ................................... 8-28
Removing a wheel ................................... 8-29
Installing a wheel ..................................... 8-30
Troubleshooting ....................................... 8-31
Troubleshooting chart .............................. 8-32
CLEANING AND STORAGE ..........................9-1
Cleaning ..................................................... 9-1
Storage ...................................................... 9-2
SPECIFICATIONS .......................................10-1
CONSUMER INFORMATION.......................11-1
Identification numbers .............................. 11-1

7-19
1
2
3
4
5
67
8
9
10
11

Owner’s Manual. Remember that wet brakes
may have reduced stopping ability. Test your
brakes after leaving water. If necessary, apply
them several times to let friction dry out the lin-
ings. If the ATV is operated through deep or
fast flowing water, the tires may float, causing
loss of traction and loss of control, which
could lead to an accident.
Test your brakes after leaving the water. Do not
continue to ride your ATV without verifying that you
have regained proper braking ability.CAUTION:
ECB00240
After riding your ATV in water, be sure to drain
the trapped water by removing the check hose
at the bottom of the air filter case. Wash the
ATV in fresh water if it has been operated in
salt water or muddy conditions.

8-7
1
2
3
4
5
6
78
9
10
11

EBU23060
NOTE:

The air filter needs more frequent service if you are riding in unusually wet or dusty areas.

8-13
1
2
3
4
5
6
78
9
10
11

To 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 cap and the fi-
nal gear oil drain bolt to drain the oil from the
final gear case.
4. Install the drain bolt, and then tighten it to the
specified torque.5. Add the specified amount of the recommend-
ed final gear oil, and then check the oil level.CAUTION:
ECB00420
Be sure no foreign material enters the final
gear case.
6. Install and tighten the oil filler cap.
7. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
EBU23803
Cleaning the air filter element
The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty
areas.
NOTE:

There is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
1. Final gear oil drain bolt
Tightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
1

Recommended final gear oil:
See page 10-1.
Oil quantity:
0.12 L (0.13 US qt) (0.11 Imp.qt)

8-14
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2
3
4
5
6
78
9
10
11

the hose and clean the air filter element and air fil-
ter case.
1. Remove the panel shown by removing the
bolts.
1. Air filter case check hose
1

1. Panel
2. Bolt
122

8-15
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2
3
4
5
6
78
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10
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2. Remove the air filter case cover by unhooking
the holders.3. Unhook the holder holding the air filter ele-
ment, and then pull out the sponge material
from the air filter element.
4. Wash the sponge material gently but thor-
oughly in solvent.
WARNING

EWB01940
Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-
1. Air filter case cover
2. Air filter case holder
2
2
1

1. Air filter element holder
2. Sponge material
1
2

8-16
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2
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5
6
78
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11

plode.
5. Squeeze the excess solvent out of the sponge
material and let it dry.
CAUTION:

ECB00440
Do not twist the sponge material when squeez-
ing it.
6. Check the sponge material and replace it if
damaged.
7. Apply a quality foam air filter oil to the sponge
material.
NOTE:

The sponge material should be wet but not drip-
ping.
8. Install the sponge material into the air filter el-
ement.
9. Place the air filter element in the original posi-
tion, and then hook the holder.
10. Install the air filter case cover by hooking the
holders onto the air filter case.
11. Install the panel by installing the bolts.
NOTE:

The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions.
CAUTION:

ECB00460

Make sure that the air filter element is prop-
erly seated in the air filter case.

Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter element
will affect carburetor jetting with subsequent

10-2
1
2
3
4
5
6
7
8
910
11

Engine oil quantity:
Periodic oil change:
0.80 L (0.85 US qt) (0.70 Imp.qt)
Final gear oil:
Type:
SAE80 API GL-4 Hypoid gear oil
Quantity:
0.12 L (0.13 US qt) (0.11 Imp.qt)
Air filter:
Air filter element:
Wet element
Fuel:
Recommended fuel:
Regular unleaded gasoline only (EUR)
Unleaded gasoline only (AUS)(NZL)
Fuel tank capacity:
6.8 L (1.80 US gal) (1.50 Imp.gal)
Fuel reserve amount:
0.9 L (0.24 US gal) (0.20 Imp.gal)
Carburetor:
Manufacturer:
MIKUNI
Type x quantity:
VM16SH x 1
Spark plug (s):
Manufacturer/model:
NGK/CR7HSA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Clutch:
Clutch type:
Wet, multiple-disc automatic
Transmission:
Primary reduction system:
Spur gear
Primary reduction ratio:
65/20 (3.250)
Secondary reduction system:
Shaft drive
Secondary reduction ratio:
19/18
×
34/10 (3.588)
Transmission type:
Constant mesh 1-speed
Operation:
Left hand operation
1st:
38/14 (2.714)
Chassis:
Frame type:
Steel tube frame
Caster angle:
1.0 °
Trail:
3.4 mm (0.13 in)
Front tire:
Type:
Tubeless
Size:
AT16 x 7-7