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![YAMAHA YFZ450 2019 Owners Manual 4-9
4
3. Wipe up any spilled fuel immediately.
NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00982]
4. Tu YAMAHA YFZ450 2019 Owners Manual 4-9
4
3. Wipe up any spilled fuel immediately.
NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00982]
4. Tu](/manual-img/51/53809/w960_53809-32.png)
4-9
4
3. Wipe up any spilled fuel immediately.
NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00982]
4. Turn the fuel tank cap fully clockwise to make sure it is securely closed.EBU38170FuelMake sure there is sufficient gasoline in the tank
before starting off. Refuel if necessary.
WARNING
EWB02532Gasoline is poisonous and can cause injury or
death. Handle gasoline with care. Never siphon
gasoline by mouth. If you should swallow some
gasoline or inhale a lot of gasoline vapor, or get
some gasoline in your eyes, see your doctor
immediately. If gasoline spills on your skin,
wash with soap and water. If gasoline spills on
your clothing, change your clothes.
TIPConfirm the gasoline pump nozzle has the same
fuel identification mark. Recommended fuel:Premium unleaded gasoline only
Fuel tank capacity: 10 L (2.6 US gal, 2.2 Imp.gal)
Fuel reserve amount: 3.4 L (0.90 US gal, 0.75 Imp.gal)1. EN228 fuel identification mark
1
E5
E10
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Page 34 of 150
4-10
4About the recommended fuel
Use RON 97 octane or higher. If knocking or ping-
ing occurs, try a different brand or higher octane
gasoline. Gasoline containing ethanol can be used
if the ethanol content does not exceed 10% (E10).
Gasoline containing methanol is not recommend-
ed because it can cause damage to the fuel sys-
tem or vehicle performance problems.
NOTICEECB00071Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.
EBU26734SeatTo remove the seat
Insert your hand between the rear of the seat and
the rear fender, pull the seat lock lever and pull up
the seat at the rear.1. Seat lock lever
1
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4-11
4
To install the seat
Insert the projections on the front of the seat into
the seat holders, and then push down on the seat
at the rear to lock it in place. Make sure that the
seat is securely fitted.
EBU30054Front shock absorbers The shock absorber spring preload, rebound
damping force, and compression damping force
(fast and slow compression damping) can be ad-
justed.
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. Notes on adjusting the suspension
A special wrench can be obtained at a Yamaha
dealer to make the spring preload adjustment.
When adjusting the damping force settings, turn
the adjuster in direction (a) until it stops, and
then count the turns or clicks in direction (b).
Although a damping force adjuster may turn or
click beyond the stated minimum settings, such
adjustments are ineffective and may damage
the suspension.
1. Projection
2. Seat holder
1
2
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4-12
4
NOTICEECB00091Never turn an adjusting mechanism beyond
the minimum and maximum settings. Spring preload1. Loosen the locknut.
2. Turn the spring preload adjusting nut in direc- tion (a) to increase the spring preload and
thereby harden the suspension. Turn in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIPThe spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the greater the spring
preload. The longer distance A is, the lesser the
spring preload.
Each complete turn of the adjusting nut chang-
es distance A by 1.5 mm (0.06 in).
1. Locknut
2. Spring preload adjusting nut
3. Special wrench
(a)
(b) 2 1
3
Spring preload setting: Minimum (soft):Distance A = 302.5 mm (11.91 in)
Standard: Distance A = 293.0 mm (11.54 in)
Maximum (hard): Distance A = 282.5 mm (11.12 in)
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4-13
4
3. 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]
Rebound damping force
Turn the rebound damping force adjusting screw
in direction (a) to increase the rebound damping
force. Turn in direction (b) to decrease the re-
bound damping force.1. Distance ATightening torque: Locknut:50 N·m (5.0 kgf·m, 37 lb·ft)
1
1. Rebound damping force adjusting screwRebound damping force settings: Minimum (soft):30 click(s) in direction (b)
Standard: 16 click(s) in direction (b)
Maximum (hard): 1 click(s) in direction (b)
(a)
(b)
1
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4-14
4Compression damping force
Fast compression damping force
Turn the fast compression damping force adjust-
ing bolt in direction (a) to increase the fast com-
pression damping force. Turn in direction (b) to
decrease the fast compression damping force.
Slow compression damping force
Turn the slow compression damping force adjust-
ing screw in direction (a) to increase the slow com-
pression damping force. Turn in direction (b) to
decrease the slow compression damping force.
1. Fast compression damping force adjusting bolt
(a)
(b)1
Fast compression damping force settings:
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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4-15
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.
EBU30145Rear shock absorbersThe shock absorber spring preload, rebound
damping force, and compression damping force
(fast and slow compression damping) can be ad-
justed.
WARNING
EWB02681Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the
1. Slow compression damping force adjusting screwSlow compression damping force settings:
Minimum (soft):20 click(s) in direction (b)
Standard: 7 click(s) in direction (b)
Maximum (hard): 1 click(s) in direction (b)
(a)
(b)
1
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4-16
4rebound damping force adjusting screw or the
oil reservoir with your bare hand or skin until
the suspension components have cooled.
Notes on adjusting the suspension
A special wrench can be obtained at a Yamaha
dealer to make the spring preload adjustment.
When adjusting the damping force settings, turn
the adjuster in direction (a) until it stops, and
then count the turns or clicks in direction (b).
Although a damping force adjuster may turn or
click beyond the stated minimum settings, such
adjustments are ineffective and may damage
the suspension.NOTICEECB00091Never turn an adjusting mechanism beyond
the minimum and maximum settings. Spring preload
1. Remove the cowling. (See page 8-10.)
2. Remove the clip from the hose holder, re- move 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
UBW262E0.book Page 16 Tuesday, April 3, 2018 10:59 AM