2018 YAMAHA YFZ450R check engine

EBU17421
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 1-1
SAFETY INFORMATION ................................ 2-1
DESCRIPTION................................................ 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 4-1 Main switch ................................................. 4-1
Indicator light and warning lights ................ 4-1
Handlebar switches .................................... 4-3
Throttle lever ............................................... 4-4
Speed limiter ............................................... 4-4
Clutch lever ................................................. 4-5
Brake lever .................................................. 4-5
Brake pedal ................................................. 4-6
Parking brake lever ..................................... 4-6
Shift pedal ................................................... 4-7
Fuel tank cap............................................... 4-8
Fuel ............................................................. 4-8 Seat .......................................................... 4-10
Front shock absorbers ............................. 4-11
Rear shock absorbers .............................. 4-16
Handlebar position ................................... 4-23
PRE-OPERATION CHECKS .......................... 5-1 Fuel ............................................................. 5-4
Engine oil .................................................... 5-4
Coolant ....................................................... 5-4
Front and rear brakes ................................. 5-4
Throttle lever ............................................... 5-5
Drive chain .................................................. 5-5
Tires ............................................................ 5-5
Chassis fasteners ....................................... 5-7
Instruments, lights and switches ................ 5-7
OPERATION .................................................. 6-1 Starting the engine ..................................... 6-1
Shifting........................................................ 6-2
Engine break-in........................................... 6-4
Parking........................................................ 6-4
Parking on a slope ...................................... 6-5
Accessories and loading ............................ 6-5UBW261E0.book Page 1 Friday, May 26, 2017 9:38 AM

RIDING YOUR ATV ........................................ 7-1GETTING TO KNOW YOUR ATV ................ 7-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 7-2
BE CAREFUL WHERE YOU RIDE ............... 7-8
TURNING YOUR ATV................................ 7-11
CLIMBING UPHILL ................................... 7-13
RIDING DOWNHILL .................................. 7-16
CROSSING A SLOPE................................ 7-17
CROSSING THROUGH SHALLOW WATER .................................................... 7-18
RIDING OVER ROUGH TERRAIN ............. 7-20
SLIDING AND SKIDDING.......................... 7-20
WHAT TO DO IF... ..................................... 7-21
WHAT TO DO... ......................................... 7-22
PERIODIC MAINTENANCE AND
ADJUSTMENT................................................ 8-1 Owner’s manual and tool kit ....................... 8-2
Periodic maintenance chart: Emission control system .......................................... 8-3
Periodic maintenance chart: General maintenance and lubrication..................... 8-5
Removing and installing the cowling and panels...................................................... 8-10
Checking the spark plug ........................... 8-13
Engine oil and oil filter element ................. 8-14 Coolant ..................................................... 8-20
Cleaning the air filter element ................... 8-21
Cleaning the spark arrester ...................... 8-25
Adjusting the throttle lever free play ......... 8-27
Valve clearance......................................... 8-28
Brakes....................................................... 8-28
Checking the front and rear brake pads... 8-28
Checking the brake fluid level .................. 8-29
Changing the brake fluid .......................... 8-31
Checking the front brake lever free play... 8-31
Checking the brake pedal height.............. 8-32
Adjusting the parking brake free play ....... 8-32
Brake light switches ................................. 8-34
Adjusting the clutch lever free play .......... 8-34
Drive chain slack....................................... 8-35
Lubricating the drive chain ....................... 8-37
Checking and lubricating the cables ........ 8-38
Checking and lubricating the brake and
clutch levers ........................................... 8-39
Checking the shift pedal ........................... 8-39
Checking and lubricating the brake pedal ....................................................... 8-39
Checking the wheel hub bearings ............ 8-40
Lubricating the swingarm pivots .............. 8-40
Lubricating the upper and lower arm pivots ...................................................... 8-41
Lubricating the steering shaft ................... 8-42UBW261E0.book Page 2 Friday, May 26, 2017 9:38 AM

2-4
2In the event of an accident
1. If serious injuries are incurred, you may be safer staying next to your vehicle; it may
shield you from oncoming riders. Depending
on your injuries and position in the trail; you
must make a judgment call as to whether you
should move to a position off the trail. If you
have sustained head, neck, or back injuries,
or cannot feel your limbs, you should not
move. Keep your helmet on and remain mo-
tionless. Lie down next to your vehicle and
wait for help.
2. If less serious injuries are incurred and you can walk, then move to a position off the trail.
Check yourself for injuries and apply first aid
as needed.
3. If your injuries are light, when safe to do so, move your vehicle off the trail to avoid colli-
sions with oncoming riders. Check for injuries
and apply first aid as necessary. If you can
physically operate your vehicle, inspect your
vehicle. If the vehicle is in safe operating con-
dition and you can safely operate it, restart it
and ride gently back to camp or other known
location where you can receive medical at- tention. If necessary, contact your riding party
or local authorities to let them know where
you are and what has happened.
In the event of a breakdown 1. If your vehicle will not restart or is not in safe operating condition, turn off the main switch
and engine stop switch. If the breakdown oc-
curs at twilight or night, leave the main switch
on so that your lights may warn other riders of
your stopped vehicle.
2. Get out of danger. Check for oncoming vehi- cles and when safe, push your vehicle to the
side of the trail or even off the main trail to
avoid any possible collisions with oncoming
riders. If you cannot move your vehicle by
yourself, when safe, walk to the nearest van-
tage point and signal an oncoming rider to
help you push your vehicle to a safe place off
the trail.
3. Inspect your vehicle for any immediate haz- ardous conditions. The most obvious hazard-
ous conditions are leaking fuel and
ungrounded or broken wiring. Visually check
for broken wiring and leaking fuel. Leaking
fuel can be confirmed by the odor of gasoline.
UBW261E0.book Page 4 Friday, May 26, 2017 9:38 AM

2-5
2
4. Once immediate safety hazards are con-
firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
Aftermarket Parts, Accessories, and Modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of po-
tential safety hazards to you or others. Installing
aftermarket products or having other modifica-
tions performed to your vehicle that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious
injury or death. You are responsible for injuries re- lated to changes in the vehicle. Keep the following
guidelines in mind, as well as those provided un-
der “Loading” when mounting accessories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
gerous loss of lights or engine power.
UBW261E0.book Page 5 Friday, May 26, 2017 9:38 AM

4-2
4
EBU29923Coolant temperature warning light “ ”
This warning light comes on when the engine
overheats. When this occurs, stop the engine as
soon as it is safe to do so and allow it to cool for
10 minutes.
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). The
warning light should come on for a few seconds,
and then go off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
vehicle.NOTICEECB00011The engine may overheat if the ATV is over-
loaded. In this case, reduce the load to spec-
ification.
 Start the engine after making sure that the
warning light is out. Continuous use while
the warning light is on may cause damage to
the engine.
EBU29933Fuel level warning light “ ”
This warning light comes on when the fuel level
drops below approximately 3.4 L (0.90 US gal,
0.75 Imp.gal). When this occurs, refuel as soon as
possible.
The electrical circuit of the warning light can be
checked by setting the engine stop switch to “ ”
and turning the key to “ ” (on). The warning light
should come on for a few seconds, and then go
off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.EBU29943Engine trouble warning light “ ”
This warning light comes on or flashes when an
electrical circuit monitoring the engine is not work-
ing correctly. When this occurs, have a Yamaha
dealer check the self-diagnosis system.
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). The
warning light should come on for a few seconds,
and then go off.
UBW261E0.book Page 2 Friday, May 26, 2017 9:38 AM

4-3
4
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.
EBU18067Handlebar switchesEBU18081Engine stop switch “ / ”
Set this switch to “ ” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this switch to stop the engine in an emergency situa-
tion. The engine will not start or run when this
switch is set to “ ”.
EBU18102Start switch “ ”
Push this switch to crank the engine with the start-
er. See the starting instructions on page 6-1 prior
to starting the engine.EBU18157Light switch “ / /OFF”
Set this switch to “ ” to turn on the low beams
and the taillight. Set the switch to “ ” to turn on
the high beams and the taillight. Set the switch to
“OFF” to turn off all the lights.NOTICEECB00046Do not use the headlights with the engine
turned off for an extended period of time. The
battery may discharge to the point that the
starter will not have enough power to crank the
engine. If this should happen, remove the bat-
tery and recharge it. (See page 8-42.)
1. Light switch “ / /OFF”
2. Engine stop switch “ / ”
3. Start switch “ ”
1
23
UBW261E0.book Page 3 Friday, May 26, 2017 9:38 AM

4-4
4
EBU18284Throttle leverPush the throttle lever to increase engine speed
and the speed of the ATV. Because the throttle is
spring-loaded, the ATV will decelerate and the en-
gine will return to an idle any time the throttle lever
is released.TIPBefore starting the engine, check the throttle to be
sure it is operating smoothly. Make sure it returns
to the idle position as soon as the lever is released.
EBU18325Speed limiterThe speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum.
Adjusting the speed limiter1. Loosen the locknut.
2. To increase the maximum engine poweravailable and the maximum speed of the ATV,
turn the adjusting screw in direction (a). To
decrease the maximum engine power avail-
able and the maximum speed of the ATV, turn
1. Throttle lever
1
1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
3
12
(a)
(b)
UBW261E0.book Page 4 Friday, May 26, 2017 9:38 AM

4-9
4
TIPWhen refueling, check that the gasoline pump
nozzle has the same identification mark. NOTICEECB00071Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.
1. Maximum fuel level
2. Fuel tank filler tubeRecommended fuel:Premium unleaded gasoline, octane 97 or
higher
Fuel tank capacity: 10.0 L (2.64 US gal, 2.20 Imp.gal)
Fuel reserve amount: 3.4 L (0.90 US gal, 0.75 Imp.gal)
2
1
1. EN228 fuel identification mark
E10
1
UBW261E0.book Page 9 Friday, May 26, 2017 9:38 AM