2007 YAMAHA WR 450F length

6 - 14
–+ELECELECTRIC STARTING SYSTEM
5. Measure:
•Brush length a
Out of specification → Replace the
brushes as a set.
Min. brush length:
3.5 mm (0.14 in)
6. Measure:
•Brush spring force
Out of specification → Replace the brush
springs as a set.
Brush spring force:
3.92 ~ 5.88 N
(400 ~ 600 gf, 14.1 ~ 21.2 oz)
ASSEMBLY
1. Install:
•Brush spring 1
•Brush 2
2. Install:
•Armature assembly 1
Install while holding down the brush using
a thin screw driver.
CAUTION:
Be careful not to damage the brush during
installation.

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TUN
EC72B000
Rear suspension setting
The rear suspension setting should be made
depending on the rider’s feeling of an actual
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.
•Change the compression damping.
EC72C001
Choosing set length
1. Place a stand or block under the engine to
put the rear wheel above the floor, and
measure the length a between the rear
wheel axle center and the rear fender hold-
ing 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 adjust-
ment by turning the spring adjuster 2 to
achieve the standard figure from the sub-
traction of the length b from the length a.
Standard figure:
90 ~ 100 mm (3.5 ~ 3.9 in)
SETTING

7 - 16
TUNSETTING
NOTE:
•If the machine is new and after it is broken in,
the same set length of the spring may
change because of the initial fatigue, etc. of
the spring. Therefore, be sure to make re-
evaluation.
•If the standard figure cannot be achieved by
adjusting the spring adjuster and changing
the spring set length, replace the spring with
an optional one and make re-adjustment.
EC72G001
Setting of spring after replacement
After replacement, be sure to adjust the spring
to the set length [sunken length 90 ~ 100 mm
(3.5 ~ 3.9 in)] and set it.
1. Use of soft spring
•Set the soft spring for less rebound
damping to compensate for its less spring
load. Run with the rebound damping
adjuster one or two clicks on the softer
side and readjust it to suit your prefer-
ence.
2. Use of stiff spring
•Set the soft spring for more rebound
damping to compensate for its greater
spring load. Run with the rebound damp-
ing adjuster one or two clicks on the
stiffer side and readjust it to suit your
preference.
*Adjusting the rebound damping will be fol-
lowed more or less by a change in the com-
pression damping. For correction, turn the
low compression damping adjuster on the
softer side.

7 - 17
TUN
CAUTION:
When using a rear cushion other than cur-
rently installed, use the one whose overall
length a does not exceed the standard as
it may result in faulty performance. Never
use one whose overall length is greater
than standard.
Length a of standard shock:
488.5 mm (19.23 in)
SETTING

7 - 18
TUNSETTING
EC72Q000
Rear shock absorber setting parts
•Rear shock spring 1
NOTE:
The I.D. color a is marked at the end of the
spring.
TYPESPRING
RATESPRING
PART NUMBERI.D.
COLOR/
POINTSPRING
FREE
LENGTH
SOFT4.3
4.5
4.7
4.9
5.1
5.35UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30
5UN-22212-40
5UN-22212-50Brown/1
Green/1
Red/1
Black/1
Blue/1
Yellow/1260
260
260
260
260
260
STD 5.5 5UN-22212-60 Pink/1 260
STIFF 5.7 5UN-22212-70 White/1 260
•Extent of adjustment (spring length)
SPRING FREE
LENGTHEXTENT OF
ADJUSTMENT
b
260 mm (10.24 in)238.5 ~ 258.5 mm
(9.39 ~ 10.18 in)

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TUNSETTING
EC72H002
Suspension setting
•Front fork
NOTE:
•If any of the following symptoms is experienced with the standard position as the base, make
resetting by reference to the adjustment procedure given in the same chart.
•Before any change, set the rear shock absorber sunken length to the standard figure 90 ~ 100 mm
(3.5 ~ 3.9 in).
SymptomSection
Check Adjust
JumpLarge
gapMedium
gapSmall
gap
Stiff over entire rangeCompression damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil level (oil amount) Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Spring Replace with soft spring.
Unsmooth movement
over entire rangeOuter tube
Check for any bends, dents, and other noticeable
scars, etc. If any, replace affected parts.
Inner tube
Under bracket tightening
torqueRetighten to specified torque.
Poor initial
movementRebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil seal Apply grease in oil seal wall.
Soft over entire
range, bottoming outCompression damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Oil level (oil amount) Increase oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Spring Replace with stiff spring.
Stiff toward stroke
endOil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
Soft toward stroke
end, bottoming outOil level (oil amount) Increase oil level by about 5 mm (0.2 in).
Stiff initial movement Compression dampingTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low front, tending to
lower front postureCompression damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in)
when one passenger is astride seat (lower rear pos-
ture).
Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
“Obtrusive” front,
tending to upper front
postureCompression damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end Set sunken length for 90 ~ 95 mm (3.5 ~ 3.7 in)
when one passenger is astride seat (upper rear pos-
ture).
Spring Replace with soft spring.
Oil lever (oil amount) Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).

7 - 20
TUNSETTING
•Rear shock absorber
NOTE:
•If any of the following symptoms is experienced with the standard position as the base, make
resetting 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.
SymptomSection
Check Adjust
JumpLarge
gapMedium
gapSmall
gap
Stiff, tending to sinkRebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Spring set length Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in)
when one passenger is astride seat.
Spongy and unstableRebound damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Low compression damp-
ingTurn adjuster clockwise (about 1 click) to increase
damping.
Spring Replace with stiff spring.
Heavy and draggingRebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Spring Replace with soft spring.
Poor road grippingRebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low compression damp-
ingTurn adjuster clockwise (about 1 clicks) to increase
damping.
High compression damp-
ingTurn adjuster clockwise (about 1/6 clicks) to
increase damping.
Spring set length Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in)
when one passenger is astride seat.
Spring Replace with soft spring.
Bottoming outHigh compression damp-
ingTurn adjuster clockwise (about 1/6 turn) to increase
damping.
Spring set length Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in)
when one passenger in astride seat.
Spring Replace with stiff spring.
BouncingRebound damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Spring Replace with soft spring.
Stiff travelHigh compression damp-
ingTurn adjuster counterclockwise (about 1/6 turn) to
decrease damping.
Spring set length Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in)
when one passenger is astride seat.
Spring Replace with soft spring.