Page 102 of 150

9-19
92. 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-
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]
1. Maximum level mark
2. Minimum level mark
12
1. Coolant reservoir cap
1
UBCX61E0.book Page 19 Friday, January 22, 2021 1:54 PM
Page 104 of 150

9-21
95. Remove the coolant reservoir cap.
6. Disconnect the coolant reservoir hose on the
coolant reservoir side, and then drain the
coolant from the coolant reservoir.
7. After draining the coolant, thoroughly flush the cooling system with clean tap water.
8. Install the coolant drain bolt and its new gas- ket, and then tighten the bolt to the specified
torque. 9. Connect the coolant reservoir hose.
10. Pour the recommended coolant into the res- ervoir to the maximum level mark, and then
install the reservoir cap.
11. Pour the recommended coolant into the radi- ator until it is full, and then install the radiator
cap.
12. Start the engine, let it idle for several minutes, and then turn it off.
TIPWhile the engine is idling, check the cooling sys-
tem for leaks. 13. When the engine is cool, remove the radiatorcap to check the coolant level in the radiator.
If it is low, add sufficient coolant until it reach-
es the top of the radiator, and then install the
radiator cap.
14. Install the panel.EBU2680BCleaning 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.
1. Coolant reservoir cap
2. Coolant reservoir hoseTightening torque: Coolant drain bolt:11 N·m (1.1 kgf·m, 8.1 lb·ft)
1
2
UBCX61E0.book Page 21 Friday, January 22, 2021 1:54 PM
Page 108 of 150

9-25
915. Insert the air filter element into the air filter
case, and then tighten the wing bolt.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter
case. Never operate the engine with the air
filter element removed. Doing so would al-
low unfiltered air to enter the engine, caus-
ing rapid engine wear and possible engine
damage. Additionally, the fuel injection
system would be affected resulting in poor
engine performance and possible over-
heating.
[ECB00763]
16. Install the air filter case cover by hooking the holders onto the air filter case. 17. Install the seat.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated
more often if the ATV is operated in extremely
dusty areas. Each time the air filter element main-
tenance is performed, check the air inlet of the air
filter case for obstructions. Check the air filter
case rubber joint to the throttle body and the rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU30863Cleaning the spark arresterSelect a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
WARNING
EWB02342Always let the exhaust system cool prior to
touching exhaust components.
Do not start the engine with the spark arrester
removed. Sparks or exhaust particulate can
cause eye injury, burns, or start a fire.
1. Washer
1
UBCX61E0.book Page 25 Friday, January 22, 2021 1:54 PM
Page 110 of 150
9-27
94. Install the gasket, tailpipe, and retainer and
align the bolt holes.
5. Install the bolts and tighten them to the spec- ified torque.
6. Install the tailpipe cover and align the bolt holes.
7. Install the bolts and tighten them to the spec- ified torque.
EBU26813Adjusting the engine idling speedThe engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance chart.TIPA diagnostic tachometer is needed to make this
adjustment. 1. Start the engine and warm it up.
2. Attach the tachometer to the spark plug lead.
3. Check the engine idling speed and, if neces-sary, adjust it to specification by turning the
idle adjusting screw. To increase the engine
idling speed, turn the idle adjusting screw in
direction (a), and to decrease it, turn the
screw in direction (b).
1. Tailpipe
2. Spark arresterTightening torque:Retainer bolt:10 N
Page 111 of 150
9-28
9
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.
EBU24049Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.TIPThe engine idling speed must be checked and ad-
justed before adjusting the throttle lever free play.
1. Idle adjusting screwEngine idling speed:1500–1700 r/min
1
(a)
(b)
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playThrottle lever free play: 2.0…4.0 mm (0.08…0.16 in)
32
4
(a)(b)
1
UBCX61E0.book Page 28 Friday, January 22, 2021 1:54 PM
Page 112 of 150

9-29
91. 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.
EBU24062Valve 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 chart.EBU24082Adjusting the reverse lock release ca-
bleThe reverse lock release cable stretches with use,
which can result in improper function. Therefore,
the reverse lock release cable should be checked
and adjusted at the intervals specified in the peri-
odic maintenance 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. EBU24132Checking the front and rear brake padsThe front and rear brake pads must be checked
for wear at the intervals specified in the periodic
maintenance chart.EBU29561Front brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost dis-
appeared, have a Yamaha dealer replace the
brake pads as a set.
UBCX61E0.book Page 29 Friday, January 22, 2021 1:54 PM
Page 123 of 150

9-40
9
EBU24886Lubricating the drive chainThe drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
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. Clean the drive chain with a drive chain clean-er and a small soft brush. NOTICE: To pre-
vent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-
pressure washers or inappropriate sol-
vents.
[ECB00572]
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.
1. O-ring
1
1
Recommended lubricant:
Yamaha cable lubricant or other suitable cable lubricant
UBCX61E0.book Page 40 Friday, January 22, 2021 1:54 PM
Page 133 of 150
9-50
9
3. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING! Always use a fuse of the spec- ified rating, and never use a substitute ob-
ject in place of the proper fuse. An
improper fuse or a substitute object can
cause damage to the electrical system,
which could lead to a fire.
[EWB02173]
4. Turn on the main switch and start the engine.
5. If the fuse immediately blows again, have a Yamaha dealer check the vehicle.
6. Install the seat.
EBU30165Replacing a headlight bulbIf a headlight bulb burns out, replace it as follows. 1. Remove the headlight unit by removing the bolt and pulling the headlight unit outward as
shown.
2. Remove the bulb cover.
Specified fuses:
Main fuse:30.0 A
Headlight fuse: 10.0 A
Ignition fuse: 10.0 A
Signaling system fuse: 10.0 A
Radiator fan motor fuse: 20.0 A
Fuel injection system fuse: 10.0 A1. Bolt
2. Headlight unit
2
1
UBCX61E0.book Page 50 Friday, January 22, 2021 1:54 PM