2011 YAMAHA YFZ450R Owners Manual

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4
WARNING
EWB00410These shock absorber assemblies contain
highly pressurized nitrogen gas. Read and un-
derstand the following information before han-
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.EBU30140Adjusting the rear shock absorber as-
sembly This shock absorber assembly is equipped with a
spring preload adjusting nut, a rebound damping
force adjusting screw, a compression damping
force adjusting bolt (for fast compression damp-
ing), and a compression damping force adjusting
screw (for slow compression damping).
WARNING
EWB02680Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the re-
bound damping force adjusting screw or the
oil reservoir with your bare hand or skin until
the suspension components have cooled.
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)
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4
NOTICEECB00090Never turn an adjusting mechanism beyond
the minimum and maximum settings.TIPAlthough the total number of clicks or turns of a
damping force adjusting mechanism may not ex-
actly match the following specifications due to
small differences in production, the actual number
of clicks or turns always represents the entire ad-
justing range. To obtain a precise adjustment, it
would be advisable to check the number of clicks
or turns of each damping force adjusting mecha-
nism and to modify the specifications as neces-
sary.Spring preload
1. Remove the cowling. (See page 8-9.)
2. Remove the clip from the hose holder, remove
the bolt, and then move the blow-by gas
chamber away from the vehicle.3. Loosen the clamp screw at the air filter case
side.
1. Hose holder
2. Clip
3. Bolt
4. Blow-by gas chamber
23
4
1
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4
4. Remove the air filter case holding plate by re-
moving the bolts and collars.
5. Remove the bolts, and then remove the air fil-
ter case by disconnecting it from the air intake
duct.
1. Clamp screw
1
1. Bolt
2. Collar
3. Air filter case holding plate
1
1
2
3
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4
6. Disconnect the coupler.7. Loosen the clamp screw at the throttle body
side, and then disconnect the air intake duct
from the throttle body.
8. Loosen the locknut.
9. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
1. Air filter case
2. Bolt
1. Coupler
12 2
1
1. Clamp screw
2. Air intake duct
1
2
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4
TIP
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
(0.06 in).
10. Tighten the locknut to the specified torque.
NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00081]
1. Locknut
2. Spring preload adjusting nut
3. Special wrench
213
(a)
(b)
Spring preload setting:
Minimum (soft):
Distance A = 273.5 mm (10.77 in)
Standard:
Distance A = 265.0 mm (10.43 in)
Maximum (hard):
Distance A = 253.5 mm (9.98 in)1. Distance A
1
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411. Connect the air intake duct to the throttle
body, and then tighten the clamp screw at the
throttle body side. NOTICE: Make sure that
the air intake duct is properly connected to
the throttle body, and that the clamp screw
is tightened securely.
[ECB00961]
12. Connect the coupler.
13. Place the air filter case in the original position,
connect the air intake duct to the air filter case,
and then tighten the clamp screw at the air fil-
ter case side. NOTICE: Make sure that the
air intake duct is properly connected to the
air filter case, and that the clamp screw is
tightened securely.
[ECB00971]
14. Install the air filter case bolts, and then tighten
them to the specified torque.15. Install the air filter case holding plate by install-
ing the bolts and collars, and then tighten the
bolts to the specified torque.
16. Install the blow-by gas chamber by installing
the bolt, tighten the bolt to the specified
torque, and then install the clip to the hose
holder.
17. Install the cowling.
Rebound damping force
Turn the rebound damping force adjusting screw in
direction (a) to increase the rebound damping
force and thereby harden the damping, and in di-
rection (b) to decrease the rebound damping force
and thereby soften the damping. Tightening torque:
Locknut:
30 Nm (3.0 m·kgf, 22 ft·lbf)
Tightening torque:
Air filter case bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Tightening torque:
Air filter case holding plate bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Tightening torque:
Blow-by gas chamber bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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4 Compression damping force
Remove the seat to make this adjustment. (See
page 4-10.) If the adjustment is difficult, it may be
necessary to remove panels A and C. (See page
8-9.)
Compression damping force (for fast compression
damping)To increase the compression damping force and
thereby harden the compression damping, turn the
compression damping force adjusting bolt in direc-
tion (a). To decrease the compression damping
force and thereby soften the compression damp-
ing, turn the adjusting bolt in direction (b).
1. Rebound damping force adjusting screwRebound 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)
1
(a) (b)
1. Compression damping force adjusting bolt (for fast
compression damping)
(a) (b)1
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4
Compression damping force (for slow compres-
sion damping)To increase the compression damping force and
thereby harden the compression damping, turn the
compression damping force adjusting screw in di-
rection (a). To decrease the compression damping
force and thereby soften the compression damp-
ing, turn the adjusting screw in direction (b).Compression damping setting (for fast com-
pression damping):
Minimum (soft):
2 turn(s) out from the fully turned in posi-
tion
Standard:
1 turn(s) out from the fully turned in posi-
tion
Maximum (hard):
Adjusting bolt fully turned in
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:
8 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
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