YAMAHA YFZ450R 2018 Service Manual

4-17
4
3. Loosen the clamp screw at the air filter case side. 4. Remove the air filter case holding plate by re-
moving the bolts and collars.
1. Hose holder
2. Clip
3. Bolt
4. Blow-by gas chamber
2 3
4
1
1. Clamp screw
1
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4-18
45. Remove the bolts, and then remove the air fil-ter case by disconnecting it from the air in-
take duct. 6. Disconnect the coupler.
1. Bolt
2. Collar
3. Air filter case holding plate
1
1
2
3
1. Air filter case
2. Bolt
1. Coupler
1 2
2
1
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4-19
4
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.
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).
1. Clamp screw
2. Air intake duct
1
2
1. Locknut
2. Spring preload adjusting nut
3. Special wrench
213
(a)
(b)
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4-20
410. Tighten the locknut to the specified torque. NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00082]
11. 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.
[ECB00962]
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 con-
nected to the air filter case, and that the
clamp screw is tightened securely.
[ECB00972]
14. Install the air filter case bolts, and then tighten them to the specified torque.
Spring preload setting:
Minimum (soft):Distance A = 286.5 mm (11.28 in)
Standard: Distance A = 278.0 mm (10.94 in)
Maximum (hard): Distance A = 266.5 mm (10.49 in)
1. Distance A
1
Tightening torque:Locknut:30 N·m (3.0 kgf·m, 22 lb·ft)
Tightening torque: Air filter case bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
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4
15. Install the air filter case holding plate by in-
stalling 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:
Air filter case holding plate bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
Tightening torque: Blow-by gas chamber bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
1. Rebound damping force adjusting screwRebound damping setting: Minimum (soft):30 click(s) in direction (b)*
Standard: 15 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)
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4-22
4Compression 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
8-10.)
Fast compression damping force
To increase the fast compression damping force
and thereby harden the compression damping,
turn the fast compression damping force adjust-
ing bolt in direction (a). To decrease the fast com-
pression damping force and thereby soften the
compression damping, turn the adjusting bolt in
direction (b).
Slow compression damping force
To increase the slow compression damping force
and thereby harden the compression damping,
turn the slow compression damping force adjust-
ing screw in direction (a). To decrease the slow
compression damping force and thereby soften
the compression damping, turn the adjusting
screw in direction (b).
1. Fast compression damping force adjusting bolt
(a)
(b)
1
Fast compression damping setting:
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
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4
WARNING
EWB00431This 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. EBU29403Handlebar positionThe handlebar can be adjusted to one of two po-
sitions to suit the rider’s preference. Have a
Yamaha dealer adjust the position of the handle- bar.
1. Slow compression damping force adjusting screwSlow compression damping setting: Minimum (soft):20 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
1. Handlebar
1
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5
EBU19203
PRE-OPERATION CHECKS
EBU19226Inspect 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
EWB00482Failure 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:
ITEMROUTINE PAGE
Fuel • Check fuel level in fuel tank,
and add recommended fuel if neces-
sary.
• Check fuel line for leakage. Correct if necessary. 4-8, 5-4
Engine oil • Check oil level in engine oil tank, and add recommended oil to
specified level if necessary.
• Check ATV for oil leakage. Correct if necessary. 5-4, 8-14
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, 8-20
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5
Front brake• Check operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
• Check brake pads for wear, and replace if necessary.
• Check brake fluid level in reservoir, and add specified brake fluid to specified level if necessary.
• Check hydraulic system for leakage. Correct if necessary. 5-4, 8-28, 8-29, 8-31
Rear brake • Check operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
• Check brake pads for wear, and replace if necessary.
• Check brake fluid level in reservoir, and add specified brake fluid to specified level if necessary.
• Check hydraulic system for leakage. Correct if necessary. 5-4, 8-28, 8-29, 8-32
Clutch • Check operation, and correct if necessary.
• Lubricate cable if necessary.
• Check lever free play, and adjust if necessary. 8-34
Throttle lever • Make sure that operation is smooth. Lubricate cable and lever
housing if necessary.
• Check lever free play, and adjust if necessary. 5-5, 8-27
Control cables • Make sure that operation is smooth. Lubricate if necessary. 8-38
Drive chain • Check chain slack, and adjust if necessary.
• Check chain condition. Lubricate if necessary. 5-5, 8-35, 8-37
Wheels and tires • Check wheel condition, and replace if damaged.
• Check tire condition and tread depth. Replace if necessary.
• Check air pressure. Correct if necessary. 5-5
Shift pedal • Make sure that operation is smooth.
• Correct if necessary.
8-39
Brake pedal • Make sure that operation is smooth. Lubricate pedal pivoting point
if necessary. 8-39
ITEM ROUTINE PAGEUBW261E0.book Page 2 Friday, May 26, 2017 9:38 AM