YAMAHA YFZ450 2013 Service Manual

4-14
4
EBU30620Adjusting the rear shock absorber as-
sembly The spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.NOTICEECB01090Never turn the adjusting mechanism beyond
the minimum and maximum settings.Adjust the spring preload as follows.1. Remove the seat. (See page 4-12.)
2. Disconnect the hose, and then remove the hose joint from the air filter case. 3. Disconnect the hose from the air intake duct,
and then loosen the clamp screw at the carbu-
retor side.
Spring preload setting:
Minimum (soft):1
Standard: 2
Maximum (hard): 5
1. Hose
2. Hose joint
1
2
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4-15
44. Remove the bolts, and then remove the air fil-ter case by disconnecting the air intake duct
from the carburetor. 5. Loosen the locknut.
6. 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. Hose
2. Clamp screw
3. Air intake duct
12
3
1. Bolt
2. Air filter case
2
1
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4-16
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).
7. 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. Spring preload adjusting nut
2. Locknut
3. Special wrench
2
1
(a)
(b)3
Spring preload setting:
Minimum (soft):Distance A = 264.0 mm (10.39 in)
Standard: Distance A = 257.0 mm (10.12 in)
Maximum (hard): Distance A = 250.0 mm (9.84 in)1. Distance A
1
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4-17
48. Place the air filter case in the original position,
connect the air intake duct, and then tighten
the clamp screw at the carburetor side.
NOTICE: Make sure that the air intake duct
is properly connected to the carburetor,
and that the clamp screw is tightened se-
curely.
[ECB01170]
9. Install the bolts, install the hose joint, and then connect the hoses.
10. Install the seat.
WARNING
EWB00450This shock absorber assembly contains highly
pressurized nitrogen gas. If the shock absorb-
er assembly is damaged, it could explode
causing injury or property damage. Shock ab-
sorber cylinder damage could also result in
poor handling which could cause an accident.●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.
●Do not deform or damage the cylinder in any
way.●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.
Tightening torque: Locknut:44 Nm (4.4 m·kgf, 32 ft·lbf)
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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:
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 spec-
ified 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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5-2
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, 8-32, 8-33, 8-36
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, 8-32, 8-33, 8-36
Clutch Check operation, and correct if necessary.
Lubricate cable if necessary.
Check lever free play, and adjust if necessary. 8-39
Throttle lever Make sure that operation is smooth. Lubricate cable and lever hous-
ing if necessary.
Check lever free play, and adjust if necessary. 5-5, 8-31
Control cables Make sure that operation is smooth. Lubricate if necessary. 8-43
Drive chain Check chain slack, and adjust if necessary.
Check chain condition. Lubricate if necessary. 5-5, 8-41, 8-43
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.
8-45
Brake pedal Make sure that operation is smooth. Lubricate pedal pivoting point if
necessary. 8-45
ITEM ROUTINE PAGEU1PD61E0.book Page 2 Tuesday, February 14, 2012 10:06 AM

5-3
5
Brake and clutch levers Make sure that operation is smooth. Lubricate lever pivoting points if
necessary. 8-44
Chassis fasteners Make sure that all nuts, bolts and screws are properly tightened. 5-7
Instruments, lights and
switches Check operation, and correct if necessary. 5-7
ITEM ROUTINE PAGE
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5-4
5
EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-8.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-14.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-20.)TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU19712Front and rear brakes Brake lever and brake pedal●Check that there is no free play in the brake le-
ver. If there is free play, have a Yamaha dealer
check the brake system.
●Check for correct brake pedal height. (See page
8-36.) If the pedal height is incorrect, have a
Yamaha dealer adjust it.●Check the operation of the lever and pedal. They
should move smoothly and there should be a
firm feeling when the brakes are applied. If not,
have a Yamaha dealer check the brake system.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-33.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If there is any leak-
age, have a Yamaha dealer check the brake sys-
tem.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brake pads for wear. (See page 8-32.) Specified brake fluid:
DOT 4
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5-5
5
EBU19761Throttle lever Check the operation of the throttle lever. It must
open smoothly and spring back to the idle position
when released. Have a Yamaha dealer correct if
necessary.EBU19770Drive chain Check the condition of the drive chain and check
the drive chain slack. Lubricate and adjust the
drive chain as necessary. (See page 8-41.)EBU19794Tires Check tire pressure regularly to make sure it is at
the recommended specifications. Also check for
wear and damage.
Tire pressure
Use the low-pressure tire gauge to check and ad-
just tire pressures when the tires are cold. Tire
pressures must be equal on both sides.
WARNING! Operation of this vehicle with im- proper tire pressure may cause severe injury
or death from loss of control or rollover. Tire
pressure below the minimum specified could also cause the tire to dislodge from the rim un-
der severe riding conditions.
[EWB02541]
Set tire
pressures to the following specifications:
The low-pressure tire gauge is included as stan-
dard equipment. Make two measurements of the
tire pressure and use the second reading. Dust or
dirt in the gauge could cause the first reading to be
incorrect. Recommended tire pressure:
Fron t27.5 kPa (0.275 kgf/cm², 4.0 psi)
Rear 30.0 kPa (0.300 kgf/cm², 4.4 psi)
Minimum tire pressure: Fron t24.5 kPa (0.245 kgf/cm², 3.6 psi)
Rear 27.0 kPa (0.270 kgf/cm², 4.0 psi)
Maximum tire seating pressure: Fron t250 kPa (2.5 kgf/cm², 36 psi)
Rear 250 kPa (2.5 kgf/cm², 36 psi)
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5-6
5Tire wear limit
When the tire groove decreases to 3 mm (0.12 in)
due to wear, replace the tire. Tire information
This ATV is equipped with tubeless tires with
valves.
WARNING
EWB02551Use of improper tires on this ATV may cause
loss of control, increasing your risk of an acci-
dent.After extensive tests, only the tires listed below
have been approved for this model by Yamaha
Motor Co., Ltd.
1. Low-pressure tire gauge
1
1. Tire wear limit
U1PD61E0.book Page 6 Tuesday, February 14, 2012 10:06 AM