2013 YAMAHA YFZ450 check engine

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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.EBU20184Starting a cold engine NOTICEECB00150See the “Engine break-in” section on page 6-5
prior to operating the engine for the first time.1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the key to “ON” and the engine stopswitch to “ ”. 4. Shift the transmission into neutral. The neutral
indicator light should come on. If the indicator
light does not come on, have a Yamaha deal-
er 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.5. Use the starter (choke) in reference to the fig-ure:
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).
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●Always use the clutch when changing gears.
The engine, transmission and drive train are
not designed to withstand the shock of
forced shifting and can be damaged by shift-
ing without using the clutch.EBU20672Engine break-in TIP●For ATVs equipped with an odometer or an hour
meter, follow the figures given in km (mi) or the
figures given in hours.●For ATVs not equipped with an odometer or
hour meter, follow the figures given in hours.There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 20
hours. The various parts in the engine wear and
polish themselves to the correct operating clear-
ances. During this period, prolonged full-throttle
operation or any condition that might result in en-
gine overheating must be avoided.0–160 km (0–100 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160–320 km (100–200 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine through the gears freely, but do not use
full throttle at any time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00220If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.EBU20722Parking When parking the ATV, shift into first gear, stop the
engine, apply the parking brake, and then turn the
fuel cock to “OFF”.
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questions, consult an authorized ATV dealer.
WARNING! Operating this ATV with improper modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING
EWB01501●Dry grass or brush or other combustible ma-
terial accumulated around the engine area
could catch fire. Do not operate, idle, or park
the ATV in dry grass or other dry ground cov-
er. Keep the engine area free of dry grass,
brush, or other combustible material.●Someone touching the exhaust system dur-
ing or after operation could be burned. Do
not touch the hot exhaust system. Do not
park the ATV in a place where others might
be likely to touch it.The muffler and other engine parts become ex-
tremely hot during operation and remain hot after
the engine has stopped. To reduce the risk of fire
during operation or after leaving the ATV, do not let
brush, grass and other materials collect under the
vehicle, near the muffler or exhaust pipe, or next to other hot parts. Check under the vehicle after op-
erating in areas where combustible materials may
have collected. Do not idle or park the vehicle in
long dry grass or other dry ground cover.
To prevent burns, avoid touching the exhaust sys-
tem. Park the ATV in a place where pedestrians or
children are not likely to touch it.U1PD61E0.book Page 8 Tuesday, February 14, 2012 10:06 AM

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EBU21743Periodic maintenance chart for the emission control system TIP●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 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. √√√
2 Spark plug Check condition and clean, regap, or replace if
necessary. √√√√√
3 *Valves Check valve clearance and adjust if necessary. √ √√√
4 *Carburetor Check starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces- sary. √√√√
5 *Crankcase breather
system Check breather hose for cracks or other damage,
and replace if necessary. √√√
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14*Chassis fasteners Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
15 *Shock absorber as-
semblies Check operation and correct if necessary.
Check for oil leakage and replace if necessary.
√√√
16 *Rear suspension re-
lay arm and con-
necting arm
pivoting points Check operation and correct if necessary.
√√√√
17 *Steering shaft Lubricate with lithium-soap-based grease. √√√
18 *Steering system Check operation and repair or replace if damaged.
Check toe-in and adjust if necessary.
√√√√√
19 *Engine mount Check for cracks or other damage, and replace if
necessary. √√√
20 Engine oil Change.
Check ATV for oil leakage, and correct if neces-
sary. √ √√√
21 Engine oil filter ele-
ment
Replace.
√√√
22 Cooling system Check coolant level and ATV for coolant leakage,
and correct if necessary. √√√√√
Replace coolant. Every 2 years
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 320U1PD61E0.book Page 7 Tuesday, February 14, 2012 10:06 AM

8-10
8To install the panel
1. Place the panel in the original position, and
then install the quick fastener screw and the
bolts. 2. Install the seat.
EBU23245Checking the spark plug The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.1. Projection
2. Slot
1
1
2
2
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To check the spark plug
1. Check that the porcelain insulator around the center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
1
Specified spark plug:NGK/CR8E1. Spark plug gapSpark plug gap:0.7–0.8 mm (0.028–0.031 in)
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8To install the spark plug
1. Clean the surface of the spark plug gasket and its mating surface, and then wipe off any
grime from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tighten it to the specified
torque.
TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4–1/2 turn past finger tight. However,
the spark plug should be tightened to the specified
torque as soon as possible.3. Install the spark plug cap.
4. Place the fuel tank in the original position, andthen install the bolt.
5. Remove the fuel tank cap by turning it coun- terclockwise.
6. Place the panel in the original position. 7. Install the fuel tank cap by turning it clockwise.
8. Install the bolts and the quick fastener screws.
9. Install the seat.
EBU23308Engine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
Tightening torque:
Spark plug:13 Nm (1.3 m·kgf, 9.4 ft·lbf)1. Projection
2. Slot
21
U1PD61E0.book Page 14 Tuesday, February 14, 2012 10:06 AM