2007 YAMAHA YFZ450 Owners Manual

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RES
This indicates reserve. With the fuel cock lever in
this position, the fuel reserve is made available.
Turn the fuel cock lever to this position if you run
out of fuel while riding. When this occurs, refuel as
soon as possible and be sure to turn the fuel cock
lever back to “ON”!
EBU18850
Starter (choke) “”
Starting a cold engine requires a richer air-fuel mix-
ture, which is supplied by the starter (choke).
Move the starter (choke) in direction (a) to turn onthe starter (choke).
Move the starter (choke) in direction (b) to turn off
the starter (choke).
See the “Starting a cold engine” section on page
6-1 for proper operation.
EBU18890
Seat
To remove the seat
Insert your hand between the rear of the seat and
the rear fender, pull the seat lock lever upward and
pull up the seat at the rear.
1. Arrow mark positioned over “RES”
1. Starter (choke) “ ”
1
(a)(b)

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To install the seat
Insert the projections on the front of the seat into
the seat holders and push down on the seat at the
rear.
NOTE:

Make sure that the seat is securely fitted.
EBU19010
Adjusting the front shock absorber
assemblies
The spring preload, rebound damping and com-
pression damping forces of the front shock absorb-
er assemblies can be adjusted to suit the rider’s
weight and the riding conditions.WARNING
EWB00410
These shock absorber assemblies contain
highly pressurized nitrogen gas. Read and un-
derstand the following information before han-
1. Seat lock lever
1

1. Projection
2. Seat holder
1
2

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dling the shock absorber assemblies.

Do not tamper with or attempt to open the
cylinder assemblies.

Do not subject the shock absorber assem-
blies to an open flame or other high heat
source. This may cause the unit to explode
due to excessive gas pressure.

Do not deform or damage the cylinders in
any way. Cylinder damage will result in poor
damping performance.

Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
Spring preload
1. Loosen the locknut.
2. Turn the adjusting nut in direction (a) to in-
crease the spring preload and thereby harden
the suspension, and in direction (b) to de-
crease the spring preload and thereby soften
the suspension.
NOTE:


A special wrench can be obtained at a Yamaha
dealer to make this adjustment.

The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower the
spring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.5 mm
1. Spring preload adjusting nut
2. Locknut
3. Special wrench
2
1
3 (a)
(b)

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(0.06 in). 3. Tighten the locknut to the specified torque.CAUTION:
ECB00080
Always tighten the locknut against the adjust-
ing nut, and then tighten it to the specified
torque.
Rebound damping force
Turn the adjusting screw in direction (a) to increase
the rebound damping force and thereby harden
the damping, and in direction (b) to decrease the
rebound damping force and thereby soften the
damping. Spring preload setting:
Minimum (hard):
Distance A = 246.5 mm (9.7 in)
Standard:
Distance A = 255 mm (10.0 in)
Maximum (soft):
Distance A = 261.5 mm (10.3 in)
1. Distance A
1

Tightening torque:
Locknut:
30 Nm (3.0 m·kgf, 22 ft·lbf)

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Compression damping force
Turn the adjusting screw in direction (a) to increasethe compression damping force and thereby hard-
en the damping, and in direction (b) to decrease
the compression damping force and thereby soft-
en the damping.
1. Rebound damping force adjusting screw
Rebound damping setting:
Minimum (soft):
22 click(s) in direction (b)*
Standard:
11 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
(b)
(a)
1

1. Compression damping force adjusting screw
(b)(a)
1

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CAUTION:

ECB00090
Never turn an adjusting mechanism beyond
the minimum and maximum settings.
NOTE:

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
EWB00420

Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting screw or the oil res-
ervoir with your bare hand or skin until sus-
pension components have cooled.

Always adjust the shock absorber assem-
blies on the left and right side to the same
setting.
WARNING

EWB00400
Always adjust the shock absorber assemblies
on the left and right side to the same setting.
Uneven adjustment can cause poor handling
and loss of stability, which could lead to an ac-
cident.
EBU19120
Adjusting the rear shock absorber
assembly
The spring preload, rebound damping and com-
pression damping forces of the rear shock absorb-
er assembly can be adjusted to suit the rider’s Compression damping setting:
Minimum (soft):
20 click(s) in direction (b)*
Standard:
11 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)

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weight and the riding conditions.
WARNING

EWB00430
This shock absorber assembly contains highly
pressurized nitrogen gas. Read and under-
stand the following information before han-
dling the shock absorber assembly.

Do not tamper with or attempt to open the
cylinder assembly.

Do not subject the shock absorber assembly
to an open flame or other high heat source.
This may cause the unit to explode due to ex-
cessive gas pressure.

Do not deform or damage the cylinder in any
way. Cylinder damage will result in poor
damping performance.

Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
Spring preload
1. Remove the seat. (See page 4-11.)
2. Loosen the clamp screw at the carburetor
side, and then disconnect the air intake duct.3. Disconnect the hose, and then remove the air
filter case by removing the bolts.
1. Clamp screw
1

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4. Loosen the locknut.
5. Turn the adjusting nut in direction (a) to in-
crease the spring preload and thereby harden
the suspension, and in direction (b) to de-
crease the spring preload and thereby soften
the suspension.
1. Hose
1

1. Bolt
2. Air filter case
2 1