fuel YAMAHA YFZ450R 2017 User Guide

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EBU19203
PRE-OPERATION CHECKS
EBU19226Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00482Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer. Before using this vehicle, check the following points:
ITEMROUTINE PAGE
Fuel • Check fuel level in fuel tank,
and add recommended fuel if neces-
sary.
• Check fuel line for leakage. Correct if necessary. 4-9, 5-4
Engine oil • Check oil level in engine oil tank, and add recommended oil to
specified level if necessary.
• Check ATV for oil leakage. Correct if necessary. 5-4, 8-14
Coolant • Check coolant level in reservoir, and add recommended coolant to
specified level if necessary.
• Check cooling system for leakage. Correct if necessary. 5-4, 8-20
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EBU19542FuelMake sure that there is sufficient fuel in the tank.
(See page 4-9.)EBU19561Engine oilMake sure that the engine oil is at the specified
level. Add oil as necessary. (See page 8-14.)EBU19632CoolantMake sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-20.)TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture. EBU19713Front and rear brakesBrake lever and brake pedal
Check that there is no free play in the brake le-
ver. If there is free play, have a Yamaha dealer
check the brake system. 
Check for correct brake pedal height. (See page
8-31.) If the pedal height is incorrect, have a
Yamaha dealer adjust it.
 Check the operation of the lever and pedal.
They should move smoothly and there should
be a firm feeling when the brakes are applied. If
not, have a Yamaha dealer check the brake sys-
tem.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-29.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If there is any leak-
age, have a Yamaha dealer check the brake sys-
tem. Specified brake fluid:
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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 6-4
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.
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EBU21745Periodic maintenance chart for the emission control systemTIPFor ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
 For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should still be followed.
 Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills. 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 80 160 160 320
1 *Fuel line • Check fuel hoses for cracks or other damage, and
replace if necessary. √√√
• Replace. Every 5 years
2 *Spark plug • Check condition and clean, regap, or replace if
necessary. √√√√√
3 *Va l ve s • Check valve clearance and adjust if necessary. √ √√√
4 *Crankcase breath-
er system • Check breather hose for cracks or other damage,
and replace if necessary. √√√
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EBU29431TIPSome maintenance items need more frequent service if you are riding in unusually wet, dusty, sandy or
muddy areas, or at full-throttle.
 Replace the fuel hose every five years and if cracked or damaged.
 Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.23 *Moving parts and
cables •Lubricate.
√√√√
24 *Throttle lever • Check operation.
• Check throttle lever free play, and adjust if neces-
sary.
• Lubricate cable and lever housing. √√√√√
25 *Front and rear
brake switches • Check operation and correct if necessary.
√√√√√
26 *Lights and switches • Check operation and correct if necessary.
• Adjust headlight beams. √√√√√
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)
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EBU30131Removing and installing the cowling
and panelsThe cowling and panels shown need to be re-
moved to perform some of the maintenance jobs
described in this chapter. Refer to this section
each time a cowling or panel needs to be removed
and installed.
EBU29596Panel A
To remove the panel1. Remove the seat. (See page 4-10.)
2. Remove the fuel tank cap by turning it coun-terclockwise. (See page 4-8.) NOTICE: Make
sure that no foreign material enters the
fuel tank.
[ECB01052]
3. Loosen the quick fasteners.
1. Panel A
2. Panel B
3. Cowling
1
2
3
1. Panel C
1
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84. Remove the quick fasteners, and then slide
the panel backward and pull upward. 5. Install the fuel tank cap by turning it clock-
wise.
To install the panel
1. Remove the fuel tank cap by turning it coun- terclockwise.
2. Place the panel in the original position, and then install the quick fasteners. NOTICE:
When installing the panel, be sure not to
pinch the cables or wires.
[ECB00382]
3. Tighten the quick fasteners.
4. Install the fuel tank cap by turning it clock- wise.
5. Install the seat.
1. Quick fastener
1. Quick fastener
1 1
1
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14. Install the washer onto the air filter element
frame, and then insert the wing bolt into the
hole in the air filter element frame. NOTICE:
Be sure to install the washer with its
curved side facing outward as shown.
[ECB00454]
15. 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.
1. Air filter element seat
1
1. Washer
1
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WARNING
EWB02341Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components. EBU29703Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 2.0–4.0
mm (0.08–0.16 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.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
Tightening torque:
Tailpipe cover bolt:8 N·m (0.8 kgf·m, 5.8 lb·ft)1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
32
4
(a)(b)
1
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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.
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)
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