2012 YAMAHA YFZ450R suspension

4-12
4
WARNING
EWB02491
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. Uneven adjustment can cause poor
handling and loss of stability, which could
lead to an accident.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, itwould 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. Loosen the locknut.
2. 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. Locknut
2. Spring preload adjusting nut
3. Special wrench
(a)
(b) 2 1
3
U18P66E0.book Page 12 Monday, May 16, 2011 4:23 PM

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)
U18P66E0.book Page 16 Monday, May 16, 2011 4:23 PM

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
U18P66E0.book Page 19 Monday, May 16, 2011 4:23 PM

8-7
8
14*Chassis fasteners 
Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
15 *Shock absorber as-
semblies 
Check operation and correct if necessary.
 Check for oil leakage and replace if necessary. √√√
16 *Rear suspension re-
lay arm and con-
necting arm
pivoting points 
Check operation and correct if necessary. √√√√
17 *Steering shaft Lubricate with lithium-soap-based grease. √√√
18 *Steering system 
Check operation and repair or replace if damaged.
 Check toe-in and adjust if necessary. √√√√√
19 Engine oil 
Change.
 Check ATV for oil leakage, and correct if neces-
sary. √ √√√
20 Engine oil filter ele-
ment 
Replace. √√√
21 *Cooling system 
Check coolant level and ATV for coolant leakage,
and correct if necessary. √√√√√
 Replace coolant. Every 2 years
22 *Moving parts and
cables 
Lubricate. √√√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320U18P66E0.book Page 7 Monday, May 16, 2011 4:23 PM

10-4
10
Front brake:Type:Disc brake
Operation:
Right hand operation
Specified brake fluid: DOT 4Rear brake:Type:
Disc brake
Operation: Right foot operation
Specified brake fluid: DOT 4Front suspension:Type:Double wishbone
Spring/shock absorber type: Coil spring/gas-oil damper
Wheel travel:
250 mm (9.9 in)Rear suspension:Type:Swingarm (link suspension)
Spring/shock absorber type:
Coil spring/gas-oil damper
Wheel travel: 280 mm (11.0 in)Electrical system:Ignition system:
TCI Charging system:
AC magneto
Battery:Model:
YTZ7S
Voltage, capacity: 12 V, 6.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage × quantity:Headlight:
12 V, 30.0/30.0 W × 2
Tail/brake light:
LED
Neutral indicator light: LED
Fuel level warning light: LED
Coolant temperature warning light:
LED
Engine trouble warning light: LEDFuse:Fuse:
20.0 A
U18P66E0.book Page 4 Monday, May 16, 2011 4:23 PM

Maintenance and lubrication chart ................................. 8-5
Maintenance chart, emission control system ................. 8-3
Model label ................................................................... 11-2NNeutral indicator light ..................................................... 4-2OOwner’s manual and tool kit ........................................... 8-2PParking ........................................................................... 6-4
Parking brake free play, adjusting ................................ 8-34
Parking brake lever ........................................................ 4-7
Parking on a slope ......................................................... 6-5
Part locations ................................................................. 3-1RRiding your ATV ............................................................. 7-1SSafety information .......................................................... 2-1
Seat .............................................................................. 4-10
Shifting ........................................................................... 6-2
Shift pedal ...................................................................... 4-8
Shift pedal, checking .................................................... 8-42
Shock absorber assemblies, adjusting the front .......... 4-11
Shock absorber assembly, adjusting the rear .............. 4-16
Spark arrester, cleaning ............................................... 8-27
Spark plug, checking .................................................... 8-15
Specifications ............................................................... 10-1
Speed limiter .................................................................. 4-5
Start switch ..................................................................... 4-4
Steering shaft, lubricating ............................................. 8-44
Storage ........................................................................... 9-2
Suspension, lubricating the upper and lower arm
pivots .......................................................................... 8-43 Swingarm pivots, lubricating ........................................ 8-43
TTail/brake light .............................................................. 8-50
Throttle lever ........................................................... 4-4, 5-5
Throttle lever free play, adjusting ................................. 8-29
Tires ............................................................................... 5-5
Troubleshooting ........................................................... 8-52
Troubleshooting charts ................................................. 8-53VValve clearance ............................................................ 8-30
Vehicle identification number ....................................... 11-1WWheel hub bearings, checking ..................................... 8-42
Wheel, installing ........................................................... 8-51
Wheel, removing .......................................................... 8-50
U18P66E0.book Page 2 Monday, May 16, 2011 4:23 PM