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4
Multi-function display
Push the select button “SEL” to switch the display
between the odometer “ODO”, the tripmeter
“TRIP”, the service tripmeter “SERVICE”, and the
hour meter “HOUR” in the following order:
ODO
→ TRIP → SERVICE → HOUR → ODO
Odometer and tripmeter
The odometer shows the total distance traveled
by the vehicle.
The tripmeter shows the distance traveled since it
was last reset.
To reset the tripmeter, push the select button
“SEL” for one second.
TIP The odometer will lock at 99999.
The tripmeter will reset and continue counting
after 9999.9 is reached. Service tripmeter
The service tripmeter shows the distance traveled
since it was reset at the last maintenance.
To reset the service tripmeter, push the select but-
ton “SEL” for one second.TIPThe service tripmeter will reset and continue
counting after 9999.9 is reached. Hour meter
The hour meter shows the total time the engine
has been running.EBU30761Self-diagnosis deviceThis model is equipped with a self-diagnosis de-
vice for various electrical circuits.
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8
EBU28788
PERIODIC MAINTENANCE AND ADJUSTMENT
EBU21677Periodic inspection, adjustment, and lubrication
will keep your vehicle in the safest and most effi-
cient condition possible. Safety is an obligation of
the vehicle owner and operator. The most impor-
tant points of vehicle inspection, adjustment, and
lubrication are explained on the following pages.
WARNING
EWB01842Failure to properly maintain the vehicle or per-
forming maintenance activities incorrectly may
increase your risk of injury or death during ser-
vice or while using the vehicle. If you are not fa-
miliar with vehicle service, have a Yamaha
dealer perform the service.
WARNING
EWB02563Turn off the engine when performing mainte-
nance unless otherwise specified.
A running engine has moving parts that can
catch on body parts or clothing and electri-
cal parts that can cause shocks or fires.
Running the engine while servicing can lead
to eye injury, burns, fire, or carbon monoxide
poisoning - possibly leading to death. See
page 2-6 for more information about carbon
monoxide.
WARNING
EWB02691Brake discs, calipers, drums, and linings can
become very hot during use. To avoid possible
burns, let brake components cool before
touching them. The intervals given in the periodic maintenance
charts should be considered as a general guide
under normal riding conditions. However, DE-
PENDING ON THE WEATHER, TERRAIN, GEO-
GRAPHICAL LOCATION, AND INDIVIDUAL USE,
THE MAINTENANCE INTERVALS MAY NEED TO
BE SHORTENED.
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8
EBU28392TIPSome maintenance items need more frequent service if you are riding in unusually wet, dusty, sandy or
muddy areas, or at full-throttle.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinder and calipers, and
change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged. UBB561E0.book Page 9 Monday, March 26, 2018 11:15 AM
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8-33
8
TIPReplace the air filter elements if damaged.
Service the air filter more frequently if you often
ride in wet or dusty areas.
There is a check hose at the bottom of the air fil-
ter case. If dust or water collects in this hose,
empty the hose and clean the air filter case and
air filter elements. 1. Park the ATV on a level surface.
2. Remove the seat. (See page 4-13.)
3. Remove the air filter case cover by unhooking
the air filter case cover holders. 4. Pull out the main air filter assembly and sub
air filter element.1. Air filter case check hose
1
1. Air filter case cover holder
2. Air filter case cover
1
12
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EBU29704Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.1. Slide the rubber cover back.
2. Loosen the locknut. 3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
1. Throttle lever free play
2. Rubber cover
3. Locknut
4. Throttle lever free play adjusting boltThrottle lever free play: 3.0–5.0 mm (0.12–0.20 in)2
4 3
1
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8-52
8
YFM45KDXK / YFM45KDHK
YFM45KPXK / YFM45KPHK / YFM45KPLK
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.
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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.
WARNING
EWB02281Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces. UBB561E0.book Page 65 Monday, March 26, 2018 11:15 AM
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10-2
10
Cooling system:Liquid cooled
Valve train: SOHC
Number of cylinders:
Single cylinder
Displacement: 421 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)
Compression ratio:
10.0 : 1
Starting system: Electric starter
Lubrication system: Wet sumpEngine oil:Recommended brand:YAMALUBE
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:2.30 L (2.43 US qt, 2.02 Imp.qt)
With oil filter removal: 2.40 L (2.54 US qt, 2.11 Imp.qt)
Final gear oil:Type:Yamaha Friction Modified Shaft Drive Gear Oil
Quantity: 0.38 L (0.40 US qt, 0.33 Imp.qt)Differential gear oil:Type:Yamaha Friction Modified Shaft Drive Gear Oil or SAE 80
API GL-4 Hypoid gear oil
Quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)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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