YAMAHA YFZ450R 2012 Service Manual

4-16
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.EBU30610Adjusting 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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4-17
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 preload1. Remove the cowling. (See page 8-11 for YFZ450RB or 8-14 for YFZ450RSEB.)
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
2 3
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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4-19
46. 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
1 2
2
1
1. Clamp screw
2. Air intake duct
1
2
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4-20
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
2 13
(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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4-21
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. Connect the air filter case to the air intake duct, place the air filter case in the original po-
sition, and then tighten the clamp screw at the
air filter 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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4-22
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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4-23
4Compression 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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4-24
4
WARNING
EWB00430This 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.EBU29401Handlebar 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
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5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM ROUTINE PAGE
Fuel 
Check fuel level in fuel tank, and add recommended fuel if neces-
sary.
 Check fuel line for leakage. Correct if necessary. 4-9, 5-4
Engine oil 
Check oil level in engine oil tank, and add recommended oil to spec-
ified level if necessary.
 Check ATV for oil leakage. Correct if necessary. 5-4, 8-16
Coolant 
Check coolant level in reservoir, and add recommended coolant to
specified level if necessary.
 Check cooling system for leakage. Correct if necessary. 5-4, 8-22
U18P66E0.book Page 1 Monday, May 16, 2011 4:23 PM