2021 YAMAHA YFZ50 checking oil

Accessories and loading ............................. 7-5
RIDING YOUR ATV ........................................ 8-1 GETTING TO KNOW YOUR ATV ................ 8-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 8-2
BE CAREFUL WHERE YOU RIDE ............... 8-9
TURNING YOUR ATV................................ 8-12
CLIMBING UPHILL ................................... 8-13
RIDING DOWNHILL .................................. 8-16
CROSSING A SLOPE................................ 8-17
CROSSING THROUGH SHALLOW WATER .................................................... 8-18
RIDING OVER ROUGH TERRAIN ............. 8-20
SLIDING AND SKIDDING .......................... 8-20
WHAT TO DO IF... ..................................... 8-21
PERIODIC MAINTENANCE AND
ADJUSTMENT................................................ 9-1 Owner’s Manual and tool kit ....................... 9-2
Periodic maintenance chart: Emission control system .......................................... 9-3
Periodic maintenance chart: General maintenance and lubrication..................... 9-5
Removing and installing the panel .............. 9-9
Checking the spark plug ............................. 9-9
Engine oil................................................... 9-11 Why Yamalube.......................................... 9-14
Transmission oil ........................................ 9-15
Cleaning the air filter element ................... 9-16
Cleaning the spark arrester ...................... 9-19
Adjusting the carburetor ........................... 9-20
Adjusting the engine idling speed ............ 9-20
Adjusting the throttle lever free play ......... 9-22
Valve clearance......................................... 9-22
Brakes....................................................... 9-22
Checking the front and rear brake
shoes ...................................................... 9-23
Adjusting the front brake lever free play... 9-24
Adjusting the rear brake lever free play .... 9-26
Drive chain slack....................................... 9-26
Cleaning and lubricating the drive chain ....................................................... 9-29
Checking and lubricating the cables ........ 9-29
Checking and lubricating the front and rear brake levers ..................................... 9-30
Checking the wheel hub bearings ............ 9-30
Lubricating the front arm pivots ............... 9-31
Lubricating the front knuckle pivots ......... 9-31
Lubricating the steering shaft ................... 9-32
Battery ...................................................... 9-32
Replacing the fuse .................................... 9-35
Removing a wheel .................................... 9-36
Installing a wheel ...................................... 9-36
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To check the engine oil level
1. Park the ATV on a level surface.
2. Wait for the engine to cool.
TIPIf the engine was started before checking the oil
level, wait 10 minutes. This will allow oil to settle
into the crankcase for an accurate reading. 3. Remove the engine oil filler cap and wipe the dipstick with a clean rag.
4. Insert the dipstick into the filler hole, screw it in, and then remove it again to check the oil
level. 5. If the engine oil is at or below the minimum
level mark, add sufficient quantity of the rec-
ommended engine oil. NOTICE: Be sure the
engine oil is at the correct level, otherwise
engine damage may result.
[ECB00852]
6. Check the O-ring for damage, and then insert the dipstick and tighten the engine oil filler
cap.
To change the engine oil 1. Park the ATV on a level surface.
1. Engine oil filler cap
1
1. Engine oil filler cap
2. O-ring
3. Engine oil dipstick
4. Maximum level mark
5. Minimum level mark
14523
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TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down. NOTICEECB00331Do not use oils with a diesel specification of
“CD” or oils of a higher quality than speci-
fied. In addition, do not use oils labeled “EN-
ERGY CONSERVING II” or higher.
 Make sure that no foreign material enters the
crankcase. 9. Check the engine oil filler cap O-ring for dam-
age, and then install and tighten the engine oil
filler cap.
10. 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.
11. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
EBU38620Why YamalubeYAMALUBE oil is a Genuine YAMAHA Part born ofthe engineers’ passion and belief that engine oil is
an important liquid engine component. We form
teams of specialists in the fields of mechanical en-
gineering, chemistry, electronics and track test-
ing, and have them develop the engine together
with the oil it will use. Yamalube oils take full ad-
vantage of the base oil’s qualities and blend in the
ideal balance of additives to make sure the final oil
clears our performance standards. Thus,
Yamalube mineral, semisynthetic and synthetic oils have their own distinct characters and value.
Yamaha’s experience gained over many years of research and development into oil since the
1960’s helps make Yamalube the best choice for
your Yamaha engine.
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EBU36481Cleaning and lubricating the drive
chainThe drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
chart, otherwise it will quickly wear out, especially
when riding in dusty or wet areas. Service the
drive chain as follows.NOTICEECB00562The drive chain must be lubricated after wash-
ing the ATV or riding in the rain or wet areas. 1. Remove all dirt and mud from the drive chainwith a brush or cloth.TIPFor a thorough cleaning, have a Yamaha dealer re-
move the drive chain and soak it in solvent. 2. Spray Yamaha chain lubricant or other suit-able chain lubricant on the entire chain, mak-
ing sure that all side plates and rollers have
been sufficiently oiled.
EBU24905Checking and lubricating the cablesThe operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02582Inspect cables frequently and replace if
damaged. Corrosion can result when the ca-
ble sheaths become damaged, and cables
can also become frayed or kinked, which
could restrict the operation of controls and
lead to an accident or injury.
 Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or Recommended lubricant:
Yamaha cable lubricant or other suitable cable lubricant
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INDEX
AAccessories and loading ................................................ 7-5
Air filter element, cleaning ........................................... 9-16BBattery ......................................................................... 9-32
Brake lever free play, adjusting the front ..................... 9-24
Brake lever free play (rear), adjusting .......................... 9-26
Brake lever, front ........................................................... 5-5
Brake lever, rear ............................................................. 5-6
Brake levers, checking and lubricating ........................ 9-30
Brakes .......................................................................... 9-22
Brakes, front and rear .................................................... 6-3CCables, checking and lubricating ................................ 9-29
Carburetor, adjusting ................................................... 9-20
Chassis fasteners .......................................................... 6-6
Cleaning ....................................................................... 10-1DDrive chain ..................................................................... 6-3
Drive chain, cleaning and lubricating ........................... 9-29
Drive chain slack .......................................................... 9-26EEngine break-in .............................................................. 7-3
Engine, cold start ........................................................... 7-1
Engine idling speed ..................................................... 9-20
Engine oil ..............................................................6-3, 9-11
Engine, starting a warm ................................................. 7-3
Engine stop switch ........................................................ 5-1
Engine stop switch with lanyard .................................... 5-2
FFront and rear brake shoes, checking ......................... 9-23
Front arm pivots, lubricating ........................................ 9-31
Front knuckle pivots, lubricating ................................. 9-31
Fuel ......................................................................... 5-9, 6-3
Fuel cock ..................................................................... 5-10
Fuel tank cap ................................................................. 5-8
Fuse, replacing ............................................................ 9-35HHandlebar switches ....................................................... 5-1IIdentification numbers ................................................... 1-1
Instruments and switches .............................................. 6-6KKickstarter ...................................................................... 5-7LLabel locations ............................................................... 2-1MMain switch .................................................................... 5-1
Maintenance and lubrication chart ................................ 9-5
Maintenance chart, emission control system ................ 9-3
Model label .................................................................... 1-1OOwner’s Manual and tool kit .......................................... 9-2PPanel, removing and installing ....................................... 9-9
Parking ........................................................................... 7-3
Parking brake ................................................................. 5-6
Parking on a slope ......................................................... 7-4
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Part locations ................................................................. 4-1RRiding your ATV ............................................................. 8-1SSafety information .......................................................... 3-1
Seat .............................................................................. 5-13
Shock absorber, rear ...................................................5-13
Spark arrester, cleaning ............................................... 9-19
Spark plug, checking .....................................................9-9
Specifications ............................................................... 11-1
Speed limiter .................................................................. 5-3
Starter (choke) .............................................................. 5-12
Start switch .................................................................... 5-2
Steering shaft, lubricating ............................................ 9-32
Storage ......................................................................... 10-2TThrottle lever .......................................................... 5-3, 6-3
Throttle lever free play, adjusting ................................. 9-22
Tires ............................................................................... 6-3
Transmission oil ................................................... 6-3, 9-15
Troubleshooting ........................................................... 9-37
Troubleshooting chart .................................................. 9-38VValve clearance ............................................................ 9-22
Vehicle identification number ......................................... 1-1WWheel hub bearings, checking ..................................... 9-30
Wheel, installing ........................................................... 9-36
Wheel, removing .......................................................... 9-36YYamalube ..................................................................... 9-14UBW464E0.book Page 2 Thursday, January 23, 2020 2:42 PM