2012 YAMAHA YFZ450R ignition

4-3
4
EBU29931Fuel 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 elec-
trical circuit.EBU29942Engine 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 warn-
ing 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 elec-
trical circuit.
EBU18061Handlebar switches EBU18080Engine 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 switch1. Light switch “/ /OFF”
2. Engine stop switch “/”
3. Start switch “”
1
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4-5
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EBU18323Speed limiter Your ATV is equipped with an adjustable speed
limiter. The speed limiter keeps the throttle from
fully opening, even when the throttle lever is
pushed to the maximum.1. Loosen the locknut.
2. To increase the maximum engine power avail- able and the maximum speed of the ATV, turn
the adjusting screw in direction (a). To de-
crease the maximum engine power available
and the maximum speed of the ATV, turn the
adjusting screw in direction (b). Do not turn
the adjusting screw out more than 12 mm
(0.47 in) or the throttle cable could be dam-
aged. Always make sure the throttle lever free
play is adjusted to 2.0– 4.0 mm (0.08–0.16 in).
(See page 8-29.) WARNING! Improper ad-
justment of the speed limiter and throttle
could cause throttle cable damage or im-
proper throttle operation. You could lose
control, resulting in an accident.
[EWB00241]
3. Tighten the locknut.EBU18382Clutch lever The clutch lever is located on the left handlebar
and the ignition circuit cut-off system is incorporat-
ed in the clutch lever holder. To disengage the
clutch, pull the clutch lever toward the handlebar
grip. To engage the clutch, release the clutch lever.
The clutch lever should be pulled rapidly and re-1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
3
12
(a)
(b)
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4-6
4
leased slowly for smooth clutch operation. (See
page 6-1 for a description of the ignition circuit cut-
off system.)
EBU18423Brake lever The brake lever is located on the right handlebar.
To apply the front brake, pull the brake lever to-
ward the handlebar grip.
The brake lever is equipped with a position adjust-
ing bolt. To adjust the distance between the brake
lever and the handlebar grip, hold the brake lever
away from the handlebar so it does not contact the
adjusting bolt, loosen the locknut, turn the adjust-
ing bolt, and then tighten the locknut.
EBU18432Brake pedal The brake pedal is located on the right side of the
ATV. To apply the rear brake, push down on the
brake pedal.
1. Clutch lever
1. Brake lever
2. Locknut
3. Brake lever position adjusting bolt
4. Distance between brake lever and handlebar grip
1
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6-1
6
EBU19881
OPERATION
EBU19901Read 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
EWB00631Read 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.EBU29952Starting the engine NOTICEECB00150See 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 stop
switch 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
NOTICEECB00824If a warning light does not go off, see page 4-2
for the corresponding warning light circuit
check. To avoid possible damage, do not oper-
ate the ATV if a warning light stays on.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.
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8
EBU25740Troubleshooting Although Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the fu-
el, compression, or ignition systems, for example,
can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vital
systems yourself. However, should your ATV re-
quire any repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary tools, expe-
rience, 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
EWB02280Do 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-
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EBU27693Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition. Have a Yamaha dealer
check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the battery.
DryWet
Operate the electric starter.
The engine does not start.
Have a Yamaha dealer
check the ATV.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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Front brake:Type:Disc brake
Operation:
Right hand operation
Specified brake fluid: DOT 4Rear brake:Type:
Disc brake
Operation: Right foot operation
Specified brake fluid: DOT 4Front suspension:Type:Double wishbone
Spring/shock absorber type: Coil spring/gas-oil damper
Wheel travel:
250 mm (9.9 in)Rear suspension:Type:Swingarm (link suspension)
Spring/shock absorber type:
Coil spring/gas-oil damper
Wheel travel: 280 mm (11.0 in)Electrical system:Ignition system:
TCI Charging system:
AC magneto
Battery:Model:
YTZ7S
Voltage, capacity: 12 V, 6.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage × quantity:Headlight:
12 V, 30.0/30.0 W × 2
Tail/brake light:
LED
Neutral indicator light: LED
Fuel level warning light: LED
Coolant temperature warning light:
LED
Engine trouble warning light: LEDFuse:Fuse:
20.0 A
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