2010 YAMAHA YFZ450R suspension

2-5
2
4. Once immediate safety hazards are con-
firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
Aftermarket Parts, Accessories, and Modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of po-
tential safety hazards to you or others. Installing
aftermarket products or having other modifica-
tions performed to your vehicle that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious
injury or death. You are responsible for injuries re- lated to changes in the vehicle. Keep the following
guidelines in mind, as well as those provided un-
der “Loading” when mounting accessories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
gerous loss of lights or engine power.
U1TD61E0.book Page 5 Tuesday, July 8, 2014 11:30 AM

4-12
4
WARNING
EWB02492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. NOTICEECB00091Never 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. 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
U1TD61E0.book Page 12 Tuesday, July 8, 2014 11:30 AM

4-16
4
WARNING
EWB00411These 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.
EBU30142Adjusting the rear shock absorber as-
semblyThis 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
EWB02681Suspension 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
the suspension components have cooled.
Compression damping setting (for slow com-
pression damping):
Minimum (soft):20 click(s) in direction (b)*
Standard: 7 click(s) in direction (b)*
Maximum (hard): 1 click(s) in direction (b)*
* With the adjusting screw fully turned in di- rection (a)
U1TD61E0.book Page 16 Tuesday, July 8, 2014 11:30 AM

4-19
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
1 2
2
1
1. Clamp screw
2. Air intake duct
1
2
U1TD61E0.book Page 19 Tuesday, July 8, 2014 11:30 AM

8-7
8
14*Drive chain roller • Check for wear and replace if necessary. √√√
15 *Chassis fasteners • Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
16 *Shock absorber as-
semblies • Check operation and correct if necessary.
• Check for oil leakage and replace if necessary.
√√√
17 *Rear suspension re-
lay arm and con-
necting arm
pivoting points • Check operation and correct if necessary.
√√√√
18 *Steering shaft • Lubricate with lithium-soap-based grease. √√√
19 *Steering system • Check operation and repair or replace if dam-
aged.
• Check toe-in and adjust if necessary. √√√√√
20 Engine oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √ √√√
21 Engine oil filter ele-
ment
• Replace.
√√√
22 *Cooling system • Check coolant level and ATV for coolant leakage,
and correct if necessary. √√√√√
• Replace coolant. Every 2 years
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 320U1TD61E0.book Page 7 Tuesday, July 8, 2014 11:30 AM

10-4
10
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
U1TD61E0.book Page 4 Tuesday, July 8, 2014 11:30 AM

12-2
12
Model label .................................................................. 11-1NNeutral indicator light ..................................................... 4-2OOwner’s manual and tool kit .......................................... 8-2PParking ........................................................................... 6-4
Parking brake free play, adjusting ............................... 8-32
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 ................................................... 8-39
Shock absorber assemblies, adjusting the front ......... 4-11
Shock absorber assembly, adjusting the rear ............. 4-16
Spark arrester, cleaning ............................................... 8-25
Spark plug, checking ................................................... 8-13
Specifications .............................................................. 10-1
Speed limiter .................................................................. 4-5
Start switch .................................................................... 4-4
Steering shaft, lubricating ............................................ 8-42
Storage .......................................................................... 9-2
Suspension, lubricating the upper and lower arm pivots ......................................................................... 8-41
Swingarm pivots, lubricating ....................................... 8-40
TTail/brake light ............................................................. 8-48
Throttle lever ........................................................... 4-4, 5-5
Throttle lever free play, adjusting ................................ 8-27
Tires ............................................................................... 5-5
Troubleshooting ........................................................... 8-49
Troubleshooting charts ................................................ 8-51VValve clearance ............................................................ 8-28
Vehicle identification number ...................................... 11-1WWheel hub bearings, checking .................................... 8-40
Wheel, installing ........................................................... 8-49
Wheel, removing .......................................................... 8-48
U1TD61E0.book Page 2 Tuesday, July 8, 2014 11:30 AM