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4. Check behind for people or obstacles, and
then release the brake pedal.
5. Open the throttle lever gradually and continue to watch to the rear while backing.
EBU20682Engine break-in TIPFor 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 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.EBU20691Parking When parking the ATV, stop the engine, apply the
brake pedal, shift the drive select lever into the
park position, and then turn the fuel cock to the
“ OFF ” position.
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EBU20821Parking on a slope
WARNING
EWB00860Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, place the ATV transversely across the
incline, stop the engine, shift the drive select
lever to the park position, and then block the
front and rear wheels with rocks or other ob-
jects.
Do not park the ATV at all on hills that are so
steep you could not walk up them easily.1. Bring the ATV to a stop by applying thebrakes.
2. Stop the engine.
3. With the brake pedal applied, shift the drive select lever to the park position.
4. Turn the fuel cock to “OFF ”.
EBU20910Accessories and loading EBU20921Genuine Yamaha Accessories
Choosing accessories for your ATV is an important
decision. Genuine Yamaha Accessories, which
are available only from a Yamaha dealer, have
been designed, tested, and approved by Yamaha
for use on your ATV. Many companies with no con-
nection to Yamaha manufacture parts and acces-
sories or offer other modifications for Yamaha
vehicles. Yamaha is not in a position to test the
products that these aftermarket companies pro-
duce. Therefore, Yamaha can neither endorse nor
recommend the use of accessories not sold by
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EBU21743Periodic maintenance chart for the emission control system TIPFor 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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4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24060Valve clearance The 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 and lu-
brication chart.
EBU24071Adjusting the drive select lever safety
system cable The drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted by a Yamaha dealer at the
intervals specified in the periodic maintenance and
lubrication chart.EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playU1CT61E0.book Page 38 Wednesday, April 20, 2011 6:36 PM
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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-
lot lights from water heaters or furnaces.U1CT61E0.book Page 61 Wednesday, April 20, 2011 6:36 PM
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EBU25784Troubleshooting 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.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
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.
DryWet
Open the throttle halfway and operate
the electric starter.
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EBU25933Storage Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00721]
Long-term
Before storing your ATV for several months: 1. Follow all the instructions in the “ Cleaning”
section of this chapter.
2. Turn the fuel cock lever to “OFF ”.
3. Drain the carburetor float chamber by loosen- ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if available) to prevent the fuel from deteriorat-
ing. 5. Perform the following steps to protect the cyl-
inder, piston rings, etc. from corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall with
oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
6. Lubricate all control cables and the pivoting points of all levers and pedals.
7. Check and, if necessary, correct the tire air pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U1CT61E0.book Page 2 Wednesday, April 20, 2011 6:36 PM
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EBU25961
SPECIFICATIONS
Dimensions:Overall length:1993 mm (78.5 in)
Overall width: 1093 mm (43.0 in)
Overall height:
1120 mm (44.1 in)
Seat height: 840 mm (33.1 in)
Wheelbase: 1233 mm (48.5 in)
Ground clearance:
245 mm (9.6 in)
Minimum turning radius: 3000 mm (118 in)Weight:With oil and fuel:
YFM450FAPB 287.0 kg (633 lb)
YFM45FGPB (panel wheel model) 281.0 kg (619 lb)
YFM45FGPB (cast wheel model) 284.0 kg (626 lb)
YFM45FGPHB 281.0 kg (619 lb)Noise and vibration level:Noise level (77/311/EEC):YFM45FGPB 78.3 dB(A)
YFM45FGPHB 78.3 dB(A)
Vibration on seat (EN1032, ISO5008): YFM45FGPB 0.6 m/s ²
YFM45FGPHB 0.6 m/s ² Vibration on handlebar (EN1032, ISO5008):
YFM45FGPB Will not exceed 2.5 m/s ²
YFM45FGPHB Will not exceed 2.5 m/s ²
Engine:Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement: Forward-inclined single cylinder
Displacement:
421 cm ³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)
Compression ratio: 10.00 : 1
Starting system:
Electric starter
Lubrication system: Wet sumpEngine oil:Recommended brand:
YAMALUBE
U1CT61E0.book Page 1 Wednesday, April 20, 2011 6:36 PM