STARTER YAMAHA YFZ450R 2009 Owners Manual

4-4
1
2
34
5
6
7
8
9
10
11

turned off for an extended period of time, oth-
erwise the battery may discharge to the point
that the starter motor will not operate properly.
If this should happen, remove the battery and
recharge it.
EBU18280
Throttle lever
Once the engine is running, movement of the throt-
tle lever will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring-
loaded, the ATV will decelerate, and the engine will
return to an idle any time the hand is removed from
the throttle lever.Before 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.
WARNING

EWB00250
Malfunction of the throttle could make it diffi-
cult to speed up or slow down when you need
to. This could cause an accident. Check the op-
eration of the throttle lever before you start the
engine. If the throttle does not work smoothly,
check for the cause. Correct the problem be-
fore riding the ATV or consult a Yamaha dealer.
1. Throttle lever

8-52
1
2
3
4
5
6
78
9
10
11

EBU27691
Troubleshooting 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 charge the battery if necessary.
DryWet
Operate the electric starter.

9-2
1
2
3
4
5
6
7
89
10
11

increasing the chance of an accident. Test the
brakes after washing. Apply the brakes several
times at slow speeds to let friction dry out the
linings.
EBU27260
Storage
Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.
NOTICE

ECB00720

Storing the ATV in a poorly ventilated 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 ammo-
nia) and areas where strong chemicals are
stored.
Long-term
Before storing your ATV for several months:
1. Follow all the instructions in the “Cleaning”section of this chapter.
2. Fill up the fuel tank and add fuel stabilizer (if
available) to prevent the fuel from deteriorat-
ing.
3. 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.
4. Lubricate all control cables and the pivotingSpecified amount:
7.5 ml of stabilizer to each liter of fuel (or 1 oz
of stabilizer to each gallon of fuel)

10-1
1
2
3
4
5
6
7
8
910
11

EBU25960
SPECIFICATIONS
EBU2597D
Dimensions:
Overall length:
1795 mm (70.7 in)
Overall width:
1240 mm (48.8 in)
Overall height:
1065 mm (41.9 in)
Seat height:
810 mm (31.9 in)
Wheelbase:
1270 mm (50.0 in)
Ground clearance:
235 mm (9.3 in)
Minimum turning radius:
3600 mm (142 in)
Weight:
With oil and fuel:
184.0 kg (406 lb)
Noise and vibration level:
Noise level (77/311/EEC):
84.5 dB(A) (EUR)
Vibration on seat (EN1032, ISO5008):
Will not exceed 0.5 m/s
2

(EUR)
Vibration on handlebar (EN1032, ISO5008):
Will not exceed 2.5 m/s
2

(EUR)
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
449.0 cm
3

Bore
×
stroke:
95.0
×
63.4 mm (3.74
×
2.50 in)
Compression ratio:
11.60 :1
Starting system:
Electric starter
Lubrication system:
Dry sump

Engine oil:
Type:
SAE 5W-30 or SAE 10W-30 or SAE 10W-40 or SAE
15W-40 or SAE 20W-40 or SAE 20W-50