2018 YAMAHA YFM90 checking oil

Parking ........................................................ 6-5
Parking on a slope ...................................... 6-5
Accessories and loading ............................. 6-6
RIDING YOUR ATV ........................................ 7-1 GETTING 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 Checking the spark plug............................. 8-9
Engine oil .................................................. 8-11
Transmission oil ........................................ 8-14
Cleaning the air filter element ................... 8-15
Cleaning the spark arrester ...................... 8-18
Adjusting the carburetor ........................... 8-19
Adjusting the engine idling speed ............ 8-19
Adjusting the throttle lever free play ......... 8-20
Valve clearance......................................... 8-21
Brakes....................................................... 8-21
Checking the front and rear brake
shoes ...................................................... 8-21
Adjusting the front brake lever free play... 8-22
Adjusting the rear brake lever free play .... 8-24
Drive chain slack....................................... 8-25
Lubricating the drive chain ....................... 8-27
Checking and lubricating the cables ........ 8-28
Checking and lubricating the front and rear brake levers ..................................... 8-29
Checking the wheel hub bearings ............ 8-29
Lubricating the front knuckle pivots ......... 8-30
Lubricating the steering shaft ................... 8-30
Battery ...................................................... 8-31
Replacing the fuse .................................... 8-34
Removing a wheel .................................... 8-34
Installing a wheel ...................................... 8-35
Troubleshooting........................................ 8-36
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TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4–1/2 turn past finger tight. However,
the spark plug should be tightened to the speci-
fied torque as soon as possible. 3. Install the spark plug cap.EBU37000Engine oilThe engine oil level should be checked before
each ride. In addition, the oil must be changed at
the intervals specified in the periodic maintenance
and lubrication chart.
To check the engine oil level1. Place the ATV on a level surface.
2. Check the engine oil level on a cold engine.
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. 3. Remove the engine oil filler cap, and then wipe the engine oil dipstick off 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.
Tightening torque:
Spark plug:12 N·m (1.2 kgf·m, 8.9 lb·ft)1. Engine oil filler cap
1
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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.
EBU34472Transmission oilThe transmission case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the transmission oil must be changed
at the intervals specified in the periodic mainte-
nance and lubrication chart.
To change the transmission oil1. Place the ATV on a level surface.
2. Place an oil pan under the transmission case to collect the used oil.
3. Remove the transmission oil filler cap and its O-ring from the transmission case. 4. Remove the transmission oil drain bolt and its
gasket to drain the oil from the transmission
case.
1. Transmission oil filler cap
2. O-ring12
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2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant. NOTICE: Do
not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00582]
EBU24905
Checking 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
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision.
1. O-ring
1
1
Recommended lubricant:
Yamaha cable lubricant or other suitable cable lubricant
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INDEX
AAccessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-15BBattery .......................................................................... 8-31
Brake lever free play, adjusting the front ..................... 8-22
Brake lever free play (rear), adjusting ........................... 8-24
Brake lever, front ............................................................ 4-4
Brake lever, rear ............................................................. 4-5
Brake levers, checking and lubricating ........................ 8-29
Brakes .......................................................................... 8-21
Brakes, front and rear .................................................... 5-3CCables, checking and lubricating ................................. 8-28
Carburetor, adjusting ...................................................8-19
Chassis fasteners ........................................................... 5-6
Cleaning ......................................................................... 9-1DDrive chain ..................................................................... 5-3
Drive chain, lubricating ................................................ 8-27
Drive chain slack .......................................................... 8-25
Drive select lever ............................................................ 4-6
Drive select lever and driving in reverse ........................ 6-3EEngine break-in .............................................................. 6-4
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-19
Engine oil .............................................................. 5-3, 8-11
Engine, starting a warm ................................................. 6-3Engine stop switch ......................................................... 4-2
FFront and rear brake shoes, checking ......................... 8-21
Front knuckle pivots, lubricating .................................. 8-30
Fuel ........................................................................ 4-8, 5-3
Fuel cock ...................................................................... 4-10
Fuel tank cap ................................................................. 4-8
Fuse, replacing ............................................................. 8-34HHandlebar switches ....................................................... 4-2IIdentification numbers ................................................. 11-1
Indicator lights ............................................................... 4-1
Instruments and switches .............................................. 5-6KKickstarter ...................................................................... 4-7LLabel locations ............................................................... 1-1MMain switch .................................................................... 4-1
Maintenance and lubrication chart ................................ 8-5
Maintenance chart, emission control system ................ 8-3
Model label .................................................................. 11-1NNeutral indicator light ..................................................... 4-1OOwner’s manual and tool kit .......................................... 8-2PParking ........................................................................... 6-5
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Parking brake ................................................................. 4-5
Parking on a slope ......................................................... 6-5
Part locations ................................................................. 3-1RReverse indicator light ................................................... 4-1
Riding your ATV ............................................................. 7-1SSafety information .......................................................... 2-1
Seat .............................................................................. 4-12
Shock absorber, adjusting the rear ............................. 4-14
Shock absorber assemblies, adjusting the front ......... 4-13
Spark arrester, cleaning ............................................... 8-18
Spark plug, checking ..................................................... 8-9
Specifications .............................................................. 10-1
Speed limiter .................................................................. 4-3
Starter (choke) ............................................................. 4-11
Start switch .................................................................... 4-2
Steering shaft, lubricating ............................................ 8-30
Storage .......................................................................... 9-2TThrottle lever ...........................................................4-2, 5-3
Throttle lever free play, adjusting ................................ 8-20
Tires ............................................................................... 5-3
Transmission oil ....................................................5-3, 8-14
Troubleshooting ........................................................... 8-36
Troubleshooting chart .................................................. 8-37VValve clearance ............................................................ 8-21
Vehicle identification number ...................................... 11-1WWheel hub bearings, checking .................................... 8-29Wheel, installing ........................................................... 8-35
Wheel, removing .......................................................... 8-34
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