air filter YAMAHA YFZ50 2018 Owners Manual

RIDING YOUR ATV ........................................ 7-1GETTING TO KNOW YOUR ATV ................ 7-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 7-2
BE CAREFUL WHERE YOU RIDE ............... 7-9
TURNING YOUR ATV................................ 7-12
CLIMBING UPHILL ................................... 7-13
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... ......................................... 7-22
PERIODIC MAINTENANCE AND
ADJUSTMENT................................................ 8-1 Owner’s manual and tool kit ....................... 8-2
Periodic maintenance chart for the emission control system ........................... 8-3
General maintenance and lubrication chart .......................................................... 8-5
Removing and installing the panel .............. 8-9
Checking the spark plug ............................. 8-9
Engine oil................................................... 8-11
Transmission oil ........................................ 8-14 Cleaning the air filter element ................... 8-16
Cleaning the spark arrester ...................... 8-19
Adjusting the carburetor ........................... 8-20
Adjusting the engine idling speed ............ 8-20
Adjusting the throttle lever free play ......... 8-21
Valve clearance......................................... 8-22
Brakes....................................................... 8-22
Checking the front and rear brake
shoes ...................................................... 8-22
Adjusting the front brake lever free play... 8-23
Adjusting the rear brake lever free play .... 8-25
Drive chain slack....................................... 8-26
Cleaning and lubricating the drive chain ....................................................... 8-28
Checking and lubricating the cables ........ 8-29
Checking and lubricating the front and rear brake levers ..................................... 8-29
Checking the wheel hub bearings ............ 8-30
Lubricating the front arm pivots ............... 8-30
Lubricating the front knuckle pivots ......... 8-31
Lubricating the steering shaft ................... 8-31
Battery ...................................................... 8-32
Replacing the fuse .................................... 8-35
Removing a wheel .................................... 8-35
Installing a wheel ...................................... 8-36
Troubleshooting........................................ 8-37
Troubleshooting chart .............................. 8-38UBW461E0.book Page 2 Tuesda y, January 31, 2017 5:13 PM

3-1
3
EBU17681
DESCRIPTION
EBU17691Left view
EBU17701Right view
1. Fuel tank cap
2. Fuel cock
3. Air filter
4. Engine stop switch with cord (lanyard)
5. Rear shock absorber spring preload adjuster
6. Kickstarter lever cap
7. Throttle stop screw
12
4
5
3
6
7
1. Spark arrester
2. Owner’s tool kit
3. Fuse
4. Battery
5. Spark plug
6. Engine oil filler cap
7. Transmission oil filler cap
12
3,4
5
67
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7-19
7
The ATV can be used to cross slow moving, shal-
low water of up to a maximum of 11 cm (4 in) in
depth. Before entering the water, choose your
path carefully. Enter where there is no sharp drop
off, and avoid rocks or other obstacles which may
be slippery or upset the ATV. Drive slowly and
carefully.
Test your brakes after leaving the water. If neces-
sary, apply them several times to let friction dry
out the linings. Do not continue to ride your ATV
without verifying that you have regained proper braking ability.
WARNING! Wet brakes may have
reduced stopping ability, which could cause
loss of control.
[EWB02622]
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. NOTICE: Undrained
water can cause damage or improper opera-
tion.
[ECB00842]
Wash the ATV in fresh water if it has been operat-
ed in salt water or muddy conditions.
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7-20
7RIDING OVER ROUGH TERRAIN
WARNING
EWB01652Riding improperly over obstacles could cause
loss of control or a collision. Before operating
in a new area, check for obstacles. Never at-
tempt to ride over large obstacles, such as lar-
ge rocks or fallen trees. When you go over
obstacles, always follow proper procedures as
described in the Owner’s Manual. Riding over rough terrain should be done with
caution. Look out for obstacles which could cause
damage to the ATV or could lead to an upset or accident. Be sure to keep your feet firmly mounted
on the footboards at all times. Avoid jumping the
ATV as loss of control and damage to the ATV may
result.
SLIDING AND SKIDDING
WARNING
EWB01663Skidding or sliding improperly may cause you
to lose control of this ATV. You may also regain
traction unexpectedly, which may cause the
ATV to overturn.

Learn to safely control skidding or sliding by
practicing at low speeds and on level,
smooth terrain.
 On extremely slippery surfaces, such as ice,
go slowly and be very cautious in order to re-
duce the chance of skidding or sliding out of
control. Care should be used when riding on loose or slip-
pery surfaces since the ATV may slide. If unex-
pected and uncorrected, sliding could lead to an
accident.
1. Air filter case check hose
1
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8-5
8
EBU36890General maintenance and lubrication chartTIPFor ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
 For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should still be followed.
 Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills. NO. ITEM CHECK OR MAINTENANCE
JOB INITIAL
EVERY
Whichev- er comes first month136612
km (mi) 240
(150) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320
1 Air filter element • Clean and replace if necessary. Every 20–40 hours (more often in wet or
dusty areas)
2 Air filter check hose • Clean. √√√√√
3 *Front brake • Check operation and correct if necessary.
• Check brake lever free play and adjust if neces-
sary. √√√√√
• Replace brake shoes. Whenever worn to the limit
4 *Rear brake • Check operation and correct if necessary.
• Check brake lever free play and adjust if neces-
sary. √√√√√
• Replace brake shoes. Whenever worn to the limit
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8-16
87. Check the oil filler cap O-ring for damage,
and replace it if necessary.
8. Install and tighten the oil filler cap.
9. Check the transmission case for oil leakage. If oil is leaking, check for the cause.
EBU34110Cleaning the air filter elementThe air filter element should be serviced at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are rid-
ing in unusually wet or dusty areas.TIPThere is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.
1. Park the ATV on a level surface.
2. Remove the seat. (See page 4-12.)
3. Remove the air filter case cover by unhookingthe air filter case cover holders.
Recommended oil:
See page 10-1.
Oil quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)1. Air filter case check hose
1
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8-17
8
4. Remove the air filter element, and clean it with
solvent. WARNING! Always use parts
cleaning solvent to clean the air filter ele-
ment. Never use low-flash-point solvents
or gasoline to clean the air filter element
because the engine could catch fire or ex-
plode.
[EWB03540]
5. Squeeze the excess solvent out of the air filter element and let it dry. NOTICE: Do not twist
the air filter element when squeezing it.
[ECB02310]
1. Air filter case cover
2. Air filter case cover holder
1
2
1. Air filter element
1
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8-18
86. Check the air filter element and replace it if
damaged.
7. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the element.
TIPThe air filter element should be wet but not drip-
ping. 8. Insert the air filter element into the air filtercase.
9. Install the air filter case cover by hooking the holders onto the air filter case. NOTICE:
Make sure that the air filter element is
properly seated in the air filter case. Never
operate the engine with the air filter ele- ment removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addi-
tionally, operation without the air filter ele-
ment will affect carburetor jetting with
subsequent poor performance and possi-
ble engine overheating.
[ECB00462]
10. Install the seat.TIPThe 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
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8-19
8
dusty areas. When servicing the air filter element,
be sure to check the air inlet of the air filter case
for obstructions.
EBU28904Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts.
2. Remove the tailpipe by pulling it out of the muffler, and then remove the gasket. 3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from
the spark arrester portion of the tailpipe and
inside of the tailpipe housing.
4. Check the gasket for damage, and replace it if necessary.
5. Make sure the gasket is properly positioned, then insert the tailpipe into the muffler and
align the bolt holes.
6. Install the bolts and tighten them to the spec- ified torque.1. Tailpipe bolt
1
1. Tailpipe
2. Spark arrester
3. Gasket
1
2
3
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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: Periodic oil change:0.80 L (0.85 US qt, 0.70 Imp.qt)Transmission oil:Type:
SAE 80W-90
Quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)Air filter:Air filter element:
Wet element
Fuel:Recommended fuel:Regular unleaded gasoline only
Fuel tank capacity:
5.6 L (1.48 US gal, 1.23 Imp.gal)
Fuel reserve amount: 0.7 L (0.18 US gal, 0.15 Imp.gal)Carburetor:Type × quantity:
VM12 X 1Spark plug (s):Manufacturer/model: NGK/CR6HSA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:Dry, centrifugal automaticTransmission:Secondary reduction system:Chain drive
Secondary reduction ratio: 38/13 (2.920)
Transmission type:
V-belt automatic
Operation: Centrifugal automatic typeChassis:Frame type:
Steel tube frame
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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