suspension YAMAHA WR 450F 2016 User Guide

4
TUNING
CHASSIS.......................................................................................................... 4-1
SELECTION OF THE SECONDARY REDUCTION RATIO
(SPROCKET) ............................................................................................ 4-1
DRIVE AND REAR WHEEL SPROCKETS SETTING PARTS .................. 4-1
TIRE PRESSURE............................. .......................................................... 4-1
FRONT FORK SETTING............................................................................ 4-2
CHANGE IN AMOUNT AND CHARACTERISTICS OF FORK OIL............ 4-2
SETTING OF SPRING AFTER REPLACEMENT ...................................... 4-2
FRONT FORK SETTING PARTS............................................................... 4-3
REAR SUSPENSION SETTING ................................................................ 4-3
CHOOSING SET LENGTH ........................................................................ 4-3
SETTING OF SPRING AFTER REPLACEMENT ...................................... 4-4
REAR SHOCK ABSORBER SETT ING PARTS ......................................... 4-4
SUSPENSION SETTING (FRONT FORK)................................................. 4-6
SUSPENSION SETTING (REAR SHOCK ABSORBER) ........................... 4-7

CHASSIS
4-2
• Under a stony or a hard road condition, the tire pressure should be hi gher to prevent a flat
tire.
EAS2GC1140FRONT FORK SETTING
The front fork setting should be made depend-
ing on the rider’s feeli ng of an actual run and
the circuit conditions.
The front fork setting includes the following
three factors:
1. Setting of air spring characteristics • Change the fork oil amount.
2. Setting of spring preload • Change the spring.
3. Setting of damping force
• Change the compression damping force.
• Change the rebound damping force.The spring acts on the load and the damping
force acts on the cushion travel speed.
EAS2GC1141CHANGE IN AMOUNT AND CHARACTERIS-
TICS OF FORK OIL
Damping characteristic near the final stroke
can be changed by changing the fork oil
amount.
EWA
WARNING
Adjust the oil amount in 5 cm3 (0.2 US oz,
0.2 Imp.oz) increments or decrements. Too
small oil amount causes the front fork to
produce a noise at full rebound or the rider
to feel some pressure on his hands or body.
Alternatively, too large oil amount will
cause the air spring characteristics to have
a tendency to be stiffer with the consequent
deteriorated performance and characteris-
tics. Therefore, adjust the front fork within
the specified range.
EAS2GC1142SETTING OF SPRING AFTER REPLACE-
MENT
As the front fork setting can be easily affected
by the rear suspension, take care so that the
front and the rear are balanced (in position etc.)
when setting the front fork.
1. Use of soft spring
• Change the rebound damping force.Turn out one or two clicks.
• Change the compression damping force.
Turn in one or two clicks.
TIP
Generally a soft spring gives a soft riding feel-
ing. Rebound damping tends to become stron-
ger and the front fork may sink deeply over a
series of gaps.
2. Use of stiff spring• Change the rebound damping force.
Turn in one or two clicks.
• Change the compression damping force. Turn out one or two clicks.
Extent of adjustment
100–120 kPa (1.00–1.20 kgf/cm
2,
15–18 psi)
Standard oil amount 345 cm
3 (11.66 US oz, 12.14
lmp.oz)
Extent of adjustment 300–365 cm
3 (10.14–12.34 US
oz, 10.58–12.87 Imp.oz)
A. Air spring characteristics in relation to oil amount change
B. Load
C. Stroke
1. Max. oil amount
2. Standard oil amount
3. Min. oil amount

CHASSIS
4-3
TIP
Generally a stiff spring gives a stiff riding feel-
ing. Rebound damping tends to become weak-
er, resulting in lack of a sense of contact with
the road surface or in a vibrating handlebar.
EAS2GC1143FRONT FORK SETTING PARTS
• Front fork spring “1”
TIP
The I.D. mark (slits) “a” is proved on the end of
the spring.
EAS2GC1144REAR SUSPENSION SETTING
The rear shock absorber setting should be
made depending on the rider’s feeling of an ac-
tual run and the circuit conditions.
The rear suspension setting includes the fol-
lowing two factors:
1. Setting of spring preload • Change the set length of the spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping force.
• Change the compression damping force.
EAS2GC1145CHOOSING SET LENGTH
1. Place a stand or a block under the engine to put the rear wheel above the floor, and mea-
sure the length “a” between the rear wheel
axle center and the rear fender holding bolt.
2. Remove the stand or block from the engine and, with a rider astride the seat, measure
the sunken length “b” between the rear
wheel axle center and the rear fender hold-
ing bolt.
3. Loosen the locknut “1” and make adjustment by turning the adjuster “2” to achieve the
standard figure from the subtraction of the
length “b” from the length “a”.
Type
Spring
rate N/ mm Part number I.D.
Mark
(slits)
SOFT 4.1 2GB-23141-A0 |||
4.2 2GB-23141-B0 ||||
4.3 2GB-23141-C0 |||||
4.4 2GB-23141-D0 |-|
STD 4.5 2GB-23141-40 —
2GB-23141-E0 |-||
STIFF 4.6 33D-23141-30 |-|||
a
1
Standard figure90–100 mm (3.5–3.9 in)

CHASSIS
4-6
EAS2GC1148SUSPENSION SETTING (FRONT FORK)
TIP
• If any of the following symptoms is experienced with the standard position as the base, make reset-ting by reference to the adjustment procedure given in the same chart.
• Before any change, set the rear shock absor ber sunken length to the standard figure 90–100 mm
(3.5–3.9 in).
Symptom Section
CheckAdjust
Jump Large
gap Medi-
um
gap Small
gap
Stiff over entire
range Compression
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Oil amount Decrease oil amount by about 5–10 cm
3 (0.2–0.3 US oz, 0.2–
0.4 Imp.oz).
Spring Replace with soft spring.
Unsmooth
movement over
entire range Outer tube
Inner tube
Check for any bends, dents,
other noticeable scars, etc. If
any, replace affected parts.
Slide metal Replace with a new one for ex- tended use.
Piston metal Replace with a new one for ex- tended use.
Lower bracket
tightening
torque Retighten to specified torque.
Poor initial
movement Rebound
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Oil seals Apply grease in oil seal wall.
Soft over entire
range, bottom-
ing out Compression
damping force
Turn adjuster clockwise (about
2 clicks) to increase damping.
Oil amount Increase oil amount by about 5–10 cm
3 (0.2–0.3 US oz, 0.2–
0.4 Imp.oz).
Spring Replace with stiff spring.
Stiff toward
stroke end Oil amountDecrease oil amount by about
5 cm
3 (0.2 US oz, 0.2 Imp.oz).
Soft toward
stroke end, bot-
toming out Oil amountIncrease oil amount by about 5
cm
3 (0.2 US oz, 0.2 Imp.oz).
Stiff initial
movement Compression
damping forceTurn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.

CHASSIS
4-7
EAS2GC1149SUSPENSION SETTING (REAR SHOCK ABSORBER)
TIP
• If any of the following symptoms is experienced with the standard position as the base, make reset-ting by reference to the adjustment procedure given in the same chart.
• Adjust the rebound damping in 2- click increments or decrements.
• Adjust the low compression damping in 1-click increments or decrements.
• Adjust the high compression damping in 1/6 turn increments or decrements.Low front, tend-
ing to lower
front posture
Compression
damping force
Turn adjuster clockwise (about
2 clicks) to increase damping.
Rebound
damping force Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Balance with
rear end Set sunken length for 95–100
mm (3.7–3.9 in) when one
passenger is astride seat (low-
er rear posture).
Oil amount Increase oil amount by about 5 cm
3 (0.2 US oz, 0.2 Imp.oz).
“Obtrusive”
front, tending to
upper front pos-
ture Compression
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Balance with
rear end Set sunken length for 90–95
mm (3.5–3.7 in) when one
passenger is astride seat (up-
per rear posture).
Spring Replace with soft spring.
Oil amount Decrease oil amount by about 5–10 cm
3 (0.2–0.3 US oz, 0.2–
0.4 Imp.oz).
Symptom Section
Check Adjust
Jump Large
gap Medi-
um
gap Small
gap
Stiff, tending to
sink Rebound
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Spring set
length Set sunken length for 90–100
mm (3.5–3.9 in) when one
passenger is astride seat.
Spongy and un-
stable Rebound
damping force
Turn adjuster clockwise (about
2 clicks) to increase damping.
Low compres-
sion damping Turn adjuster clockwise (about
1 click) to increase damping.
Spring Replace with stiff spring.
Symptom
Section
Check Adjust
Jump Large
gap Medi-
um
gap Small
gap

FRONT FORK
5-44
5. Check:• Base valve “1”
Wear/damage  Replace.
Contamination  Clean.
• O-rings “2”
Wear/damage  Replace.
• Base valve bushing “3” Wear/damage  Replace.
• Spring “4” Damage/fatigue  Replace the base valve.
• Air bleed screw “5”
Wear/damage  Replace.
6. Check: • Contacting surface “a”Wear/damage  Replace.
7. Check: • Adjuster “1”
• O-rings “2”
Wear/damage  Replace.EAS2GC1201ASSEMBLING THE FRONT FORK LEGSEWA
WARNING
• Make sure the oil levels in both front fork
legs are equal.
• Uneven oil levels can result in poor han-
dling and a loss of stability.
TIP
• When assembling the front fork leg, be sure to replace the following parts:
• Inner tube bushing
• Outer tube bushing
• Oil seals
• Copper washers
• Before assembling the front fork leg, make
sure that all of the components are clean.
1. Stretch the damper assembly fully.
2. Fill: • Damper assembly
ECA
NOTICE
• Be sure to use the recommended oil. Other
oils may have an adverse effect on front
fork performance.
• When disassembling and assembling the front fork leg, take care not to allow any
foreign material to enter the front fork.
3. After filling, pump the damper assembly “1” slowly up and down (about 200 mm (7.9 in)
stroke) several times to bleed the damper
assembly of air.
TIP
Avoid excessive full stroke. A stroke of 200 mm
(7.9 in) or more will cause air to enter. In this
case, repeat the steps 1 to 3.
2 1
New
New
New
2
2 1
5 4 3
a
New
Recommended oil
Yamaha Suspension Oil S1
Standard oil amount 210 cm
3 (7.10 US oz, 7.39
Imp.oz)
New
1
2

FRONT FORK
5-50
29.Install:• Adjuster “1”
(to the inner tube)
30.Fill: • Front fork leg
ECA
NOTICE
• Be sure to use the recommended oil. Other oils may have an adverse effect on front
fork performance.
• When disassembling and assembling the front fork leg, do not allow any foreign ma-
terial to enter the front fork. 31.Install:
• Damper assembly “1”
(to the outer tube)
TIP
Temporarily tighten the damper assembly.
32.Install:• Protector guide “1”
EAS2GC1202INSTALLING THE FRONT FORK LEGS
1. Install:• Front fork “1”
TIP
• Temporarily tighten the pinch bolts (lower bracket).
• Do not tighten the pinch bolts (upper bracket)
yet.
Adjuster
55 Nm (5.5 m·kgf, 40 ft·lbf)
LOCTITE®
Recommended oil Yamaha Suspension Oil S1
Standard oil amount 345 cm
3 (11.66 US oz, 12.14
lmp.oz)
Extent of adjustment 300–365 cm
3 (10.14–12.34 US
oz, 10.58–12.87 lmp.oz)
T R..
1LT
1