2021 YAMAHA YFZ450R engine coolant

7-1
7
EBU19882
OPERATION
EBU19902Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00632Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury. EBU29954Starting the engineNOTICEECB00151See the “Engine break-in” section on page 7-4
prior to operating the engine for the first time. 1. Set the parking brake.
2. Turn the key to “ ” (on) and the engine stopswitch to “ ”.
The following warning lights should come on
for a few seconds, then go off. 
Coolant temperature warning light
 Fuel level warning light
 Engine trouble warning light
NOTICEECB00826To avoid possible damage, do not operate the
ATV if a warning light does not work as de-
scribed above. 3. Shift the transmission into neutral. The neutral
indicator light should come on, if it does not
come on, have a Yamaha dealer check the
electrical circuit.TIPThis model is equipped with an ignition circuit cut-
off system. The engine can be started under the
following conditions.
The transmission is in neutral.
 The clutch is disengaged with the transmission
in gear. However, it is recommended to shift
into neutral before starting the engine. 4. Completely close the throttle lever and start
the engine by pushing the start switch.
UBKD60E0.book Page 1 Wednesday, November 18, 2020 8:39 AM

9-7
9
14*Drive chain roller • Check for wear and replace if necessary. √√√
15 *Chassis fasteners • Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
16 *Shock absorber as-
semblies • Check operation and correct if necessary.
• Check for oil leakage and replace if necessary.
√√√
17 *Rear suspension re-
lay arm and con-
necting arm
pivoting points • Check operation and correct if necessary.
√√√√
18 *Steering shaft • Lubricate with lithium-soap-based grease. √√√
19 *Steering system • Check operation and repair or replace if dam-
aged.
• Check toe-in and adjust if necessary. √√√√√
20 Engine oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √ √√√
21 Engine oil filter ele-
ment
• Replace.
√√√
22 *Cooling system • Check coolant level and ATV for coolant leakage,
and correct if necessary. √√√√√
• Replace coolant. Every 2 years
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev-
er comes first month136612
km (mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320UBKD60E0.book Page 7 Wednesday, November 18, 2020 8:39 AM

9-20
9
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.
EBU23473CoolantThe coolant level should be checked regularly. In
addition, the coolant must be changed at the in-
tervals specified in the periodic maintenance
chart.
Tightening torque:
Engine guard bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)Recommended coolant:YAMALUBE coolant
Coolant quantity: Coolant reservoir (up to full level):0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator (including all routes): 1.25 L (1.32 US qt, 1.10 Imp.qt)
UBKD60E0.book Page 20 Wednesday, November 18, 2020 8:39 AM

9-21
9
TIPIf genuine Yamaha coolant is not available, use an
ethylene glycol antifreeze containing corrosion in-
hibitors for aluminum engines and mix with dis-
tilled water at a 1:1 ratio. NOTICEECB02190Mix antifreeze with distilled water only. Howev-
er, if distilled water is not available, soft water
may be used for refilling. Do not use hard water
or salt water since they are harmful to the en-
gine. EBU27947To check the coolant level1. Park the ATV on a level surface.
2. Wait for the engine to cool for an accurate reading.
3. Look at the coolant level in the coolant reser- voir. 4. If the coolant is at or below the minimum level
mark, remove the coolant reservoir cap.
WARNING! Remove only the coolant res-
ervoir cap. Never attempt to remove the
radiator cap when the engine is hot.
[EWB02672]
5. Add coolant to the maximum level mark, andthen install the reservoir cap. NOTICE: If
coolant is not available, use distilled water
or soft tap water instead. Do not use hard
water or salt water since they are harmful
to the engine. If water has been used in-1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
1
2
3
UBKD60E0.book Page 21 Wednesday, November 18, 2020 8:39 AM

9-22
9
stead of coolant, replace it with coolant as
soon as possible, otherwise the cooling
system will not be protected against frost
and corrosion. If water has been added to
the coolant, have a Yamaha dealer check
the antifreeze content of the coolant as
soon as possible, otherwise the effective-
ness of the coolant will be reduced.
[ECB01012]
EBU29863
Changing the coolant
The coolant must be changed at the intervals
specified in the periodic maintenance chart. Have
a Yamaha dealer change the coolant. WARNING!
Never attempt to remove the radiator cap
when the engine is hot.
[EWB04300]
EBU2680B
Cleaning the air filter elementThe air filter element should be cleaned at the in-
tervals specified in the periodic maintenance
chart. Clean or, if necessary, replace the air filter
element more frequently if you are riding in unusu-
ally 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 5-10.)
3. Remove the air filter case cover by unhooking the holders.1. Air filter case check hose
1
UBKD60E0.book Page 22 Wednesday, November 18, 2020 8:39 AM

9-53
9Engine overheating
WARNING
EWB02291Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIP
Tap water can be used in an emergency. Change to the recommended coolant as soon as possible.
 The engine will tend to overheat if the radiator is caked with mud, or if the ATV is overloaded. Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
UBKD60E0.book Page 53 Wednesday, November 18, 2020 8:39 AM

11-2
11
Starting system:Electric starter
Lubrication system: Dry sumpEngine 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:1.40 L (1.48 US qt, 1.23 Imp.qt) With oil filter removal:
1.45 L (1.53 US qt, 1.28 Imp.qt)
Coolant quantity:Radiator (including all routes):
1.25 L (1.32 US qt, 1.10 Imp.qt)
Coolant reservoir (up to the maximum level mark): 0.25 L (0.26 US qt, 0.22 Imp.qt)Air filter:Air filter element:
Wet element
Air filter oil grade: Foam air-filter oilFuel:Recommended fuel:
Premium unleaded gasoline (Gasohol [E10] acceptable)
Minimum research octane: 97
Fuel tank capacity: 10 L (2.6 US gal, 2.2 Imp.gal)
Fuel reserve amount:
3.4 L (0.90 US gal, 0.75 Imp.gal)Throttle body:ID mark:1TD1Spark plug (s):Manufacturer/model:NGK/CR8E
Spark plug gap: 0.7–0.8 mm (0.028–0.031 in)
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
UBKD60E0.book Page 2 Wednesday, November 18, 2020 8:39 AM

11-4
11
Spring:Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
250 mm (9.9 in)Rear suspension:Type:Swingarm (link suspension)
Spring:
Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel: 280 mm (11.0 in)Electrical system:System voltage:12 V
Ignition system: TCI
Charging system:
AC magnetoBattery:Model:YTZ7S
Voltage, capacity:
12 V, 6.0 AhLights:Headlight:T19L, 30.0 W/30.0 W Brake/tail light:
LED
Neutral indicator light: LED
Fuel level warning light:
LED
Coolant temperature warning light: LED
Engine trouble warning light: LED
Fuses:Main fuse:20.0 AEBU30403Noise and vibration levels statement (for Eu-
rope)
The figures quoted are emission levels and are not
necessarily safe working levels. Whilst there is a
correlation between the emission and exposure
levels, this cannot be used reliably to determine
whether or not further precautions are required.
Factors that influence the actual level of exposure
of work-force include the characteristics of the
work room, the other sources of noise, etc. i.e. the
number of machines and other adjacent process-
es, and the length of time for which an operator is
exposed to the noise. Also the permissible expo-
UBKD60E0.book Page 4 Wednesday, November 18, 2020 8:39 AM