2020 YAMAHA YFZ50 recommended oil

5-1
5
EBU19203
PRE-OPERATION CHECKS
EBU19226Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00482Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer. Before using this vehicle, check the following points:
ITEMROUTINE PAGE
Fuel • Check fuel level in fuel tank,
and add recommended fuel if neces-
sary.
• Check fuel line for leakage. Correct if necessary. 4-9, 5-3
Engine oil • Check oil level in engine, and add recommended oil to specified
level if necessary.
• Check ATV for oil leakage. Correct if necessary. 5-3, 8-11
Transmission oil • Check ATV for oil leakage. Correct if necessary. 5-3, 8-15
Front brake • Check operation, and correct if necessary.
• Lubricate cable if necessary.
• Check lever free play, and adjust if necessary. 5-3, 8-23, 8-24
Rear brake • Check operation, and correct if necessary.
• Lubricate cable if necessary.
• Check lever free play, and adjust if necessary. 5-3, 8-23, 8-26
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5-3
5
EBU38000FuelMake sure there is sufficient gasoline in the tank
before starting off. Refuel if necessary. (See page
4-9.)EBU19561Engine oilMake sure that the engine oil is at the specified
level. Add oil as necessary. (See page 8-11.)EBU34490Transmission oilMake sure that the transmission oil is at the spec-
ified level. Add oil as necessary. (See page 8-15.)EBU19653Front and rear brakesBrake levers
Check for correct free play in the brake levers. If
the free play is incorrect, adjust it. (See pages
8-24 and 8-26.)
 Check operation of the levers. They should
move smoothly and there should be a firm feel-
ing when the brake is applied. If not, have the
ATV checked by a Yamaha dealer. Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance,
check the brake shoes for wear. (See page 8-23.)
EBU19762Throttle leverCheck the operation of the throttle lever. It must
open smoothly and spring back to the idle position
when released. Have a Yamaha dealer correct if
necessary.EBU19771Drive chainCheck the condition of the drive chain and check
the drive chain slack. Lubricate and adjust the
drive chain as necessary. (See page 8-26.)EBU19799TiresCheck tire pressure regularly to make sure it is at
the recommended specifications. Also check for
wear and damage.
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8-13
82. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect the used oil.
4. Remove the engine oil filler cap, and then re- move the engine oil drain bolt to drain the oil
from the crankcase. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00312]
5. Clean the oil strainer with solvent.
6. Discard the old engine oil drain bolt O-ring, and then apply a thin coat of clean engine oil
to the new O-ring.
7. Install the oil strainer, the compression spring, the new O-ring and the engine oil
drain bolt. Tighten the engine oil drain bolt to
the specified torque. NOTICE: Before in-
stalling the engine oil drain bolt, be sure to
install the O-ring, compression spring and
oil strainer.
[ECB00322]
8. Refill with the specified amount of the recom- mended engine oil.
1. Oil strainer
2. Compression spring
3. O-ring
4. Engine oil drain bolt
1234
Tightening torque:Engine oil drain bolt:25 N·m (2.5 kgf·m, 18 lb·ft)
Recommended oil: See page 10-1.
Oil quantity: 0.80 L (0.85 US qt, 0.70 Imp.qt)
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8-16
8
5. Install the transmission oil drain bolt and its
new gasket, and then tighten the bolt to the
specified torque.
6. Refill with the specified amount of the recom- mended oil. NOTICE: Make sure that no
foreign material enters the transmission
case.
[ECB03380]
7. 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. Transmission oil drain bolt
2. GasketTightening torque:Transmission oil drain bolt:30 N·m (3.0 kgf·m, 22 lb·ft)
12
Recommended oil: See page 10-1.
Oil quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)
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8-29
8
EBU36480Cleaning and lubricating the drive
chainThe drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication 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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8-33
8
TIPWear gloves and eye protection in a ventilated
area away from sparks and open flames. Wash
hands after handling.
 It is recommended to have the battery serviced
by a Yamaha dealer.
WARNING
EWB02161Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause severe burns. Avoid contact with skin,
eyes or clothing. Always shield your eyes when
working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of
ignition away. Ventilate when charging or using
in an enclosed space. KEEP OUT OF REACH OF CHILDREN.
To remove the battery
1. Remove panel A. (See page 8-9.)
2. Unhook the battery band.
3. Disconnect the negative battery lead first, then the positive battery lead by removing
their bolt. NOTICE: When removing the bat-
tery, the main switch must be off, and the
negative lead must be disconnected be-
fore the positive lead.
[ECB01002]
1. Positive battery lead (red)
2. Negative battery lead (black)
3. Battery
4. Battery band2 4
3
1
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10-2
10
Engine oil:Recommended brand:
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: 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
Air filter oil grade:
Foam air-filter oilFuel:Recommended fuel:Regular unleaded gasoline only
Minimum research octane:
91
Fuel tank capacity: 5.6 L (1.5 US gal, 1.2 Imp.gal)
Fuel reserve amount: 0.7 L (0.18 US gal, 0.15 Imp.gal)Carburetor:Type × quantity:
VM12 × 1Spark plug (s):Manufacturer/model:
NGK/CR6HSA
Spark plug gap: 0.6–0.7 mm (0.024–0.028 in)Drivetrain:Primary reduction ratio:
1.000
Secondary reduction ratio: 2.923 (38/13)
Final drive: Chain
Clutch type:
Dry, centrifugal, shoe
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
Transmission type:CVT automatic
Gear ratio: Transmission ratio:2.140–0.710 : 1
Forward gear: 10.967 (49/15 x 47/14)Front tire:Size:AT16x6.5-7
Manufacturer/model: DURO/DI2040Rear tire:Size:AT16x7-7
Manufacturer/model: DURO/DI2041Tire air pressure (measured on cold tires):Vehicle load:0.0–41.0 kg (0–90 lb)
Recommended: Front:15.0 kPa (0.150 kgf/cm², 2.2 psi)
Rear: 15.0 kPa (0.150 kgf/cm², 2.2 psi)
Minimum:
Front:12.0 kPa (0.120 kgf/cm², 1.7 psi)
Rear:
12.0 kPa (0.120 kgf/cm², 1.7 psi)
Front wheel:Rim size:7 x 5.2ATRear wheel:Rim size:7 x 5.2ATFront brake:Type:
Mechanical leading, trailing drum brakeRear brake:Type:Mechanical leading, trailing drum brakeFront suspension:Type:Swing axle
Spring: Coil spring
Shock absorber:
Gas-hydraulic damper
Wheel travel: 60 mm (2.4 in)Rear suspension:Type:
Swingarm
Spring: Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
51 mm (2.0 in)
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