2009 YAMAHA YFZ450R compression ratio

4-15
1
2
34
5
6
7
8
9
10
11
NOTICE

ECB00090
Never turn an adjusting mechanism beyond
the minimum and maximum settings.
TIP
Although the total number of clicks of a damping
force adjusting mechanism may not exactly match
the above specifications due to small differences in
production, the actual number of clicks always rep-
resents the entire adjusting range. To obtain a pre-
cise adjustment, it would be advisable to check the
number of clicks of each damping force adjusting
mechanism and to modify the specifications as
necessary.
WARNING

EWB02490

Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the
rebound damping force adjusting screw or
the oil reservoir with your bare hand or skin
until suspension components have cooled.

Always adjust the shock absorber assem-
blies on the left and right side to the same
setting.
1. Compression damping force adjusting screw (for slow
compression damping)
Compression damping setting (for slow com-
pression damping):
Minimum (soft):
18 click(s) in direction (b)*
Standard:
10 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
(a)
(b)
1

4-24
1
2
34
5
6
7
8
9
10
11

be advisable to check the number of clicks of
each damping force adjusting mechanism and
to modify the specifications as necessary.
WARNING

EWB00440
Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting screw or the oil reser-
voir with your bare hand or skin until suspen-
sion components have cooled.
EBU29400
Handlebar position
The handlebar can be adjusted to one of four posi-
tions to suit the rider’s preference. Have a Yamaha
dealer adjust the position of the handlebar.
1. Handlebar
1

8-50
1
2
3
4
5
6
78
9
10
11

of the wheel.

When installing a rear wheel, make sure its
wording “SIDE FACING OUTWARDS” faces
outwards.
3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified
torques.
EBU25740
Troubleshooting
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.
1. Arrow mark
Tightening torques:
Front wheel nut:
45 Nm (4.5 m·kgf, 32 ft·lbf)
Rear wheel nut:
45 Nm (4.5 m·kgf, 32 ft·lbf)

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