2021 YAMAHA YFZ450R service

9-43
9
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU2918BBatteryThis model is equipped with a 12-volt VRLA
(valve-regulated lead-acid) battery. There is no
need to check the electrolyte or to add distilled
water. However, the battery lead connections
need to be checked and tightened, and the bat-
tery terminals cleaned if corroded. If the battery
seems to have discharged, recharge it as soon as
possible.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 the seat. (See page 5-10.)
2. Remove the battery holding plate by remov- ing the bolts.
UBKD60E0.book Page 43 Wednesday, November 18, 2020 8:39 AM

9-50
9
EBU27484Installing a wheel1. Install the wheel with the arrow mark pointingin the forward rotating direction of the wheel,
and then install the wheel nuts.
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified torques.
EBU25741TroubleshootingAlthough Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the
fuel, compression, or ignition systems, for exam-
ple, can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vi-
tal systems yourself. However, should your ATV
require any repair, take it to a Yamaha dealer,
whose skilled technicians have the necessary
tools, experience, and know-how to service the
ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
1. Arrow mark
2. Forward rotating direction
3. Wheel nut
2
3
3
Tightening torques: Front wheel nut:45 N·m (4.5 kgf·m, 33 lb·ft)
Rear wheel nut: 45 N·m (4.5 kgf·m, 33 lb·ft)
UBKD60E0.book Page 50 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