length YAMAHA YZ125LC 2007 User Guide

5-67
CHASREAR SHOCK ABSORBER
EC5852B5
Rear shock absorber
1. Install:
9Dust seal 1
9O-ring 2
9Collar 3
NOTE:
9Apply the molybdenum disulfide grease on the
dust seal lips and collars.
9Apply the lithium soap base grease on the O-
rings.
2. Install:
9Bush 1
9Collar 2
9Dust seal 3
NOTE:
9Apply the molybdenum disulfide grease on the
bearing and dust seal lips.
9Install the dust seals with their lips facing out-
ward.
4. Adjust:
9Spring length (installed)
Refer to “REAR SHOCK ABSORBER
SPRING PRELOAD ADJUSTMENT” sec-
tion in the CHAPTER 3.
5. Tighten:
9Locknut 1
3. Tighten:
9Adjuster 1
1C3-9-32-5D 4/7/06 2:51 PM Page 26

EC72P010
Front fork setting parts
9Front fork spring 1
NOTE:
The I.D. mark (slits) ais proved on the end of
the spring.
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 follow-
ing two factors:
1. Setting of spring preload
9Change the set length of the spring.
9Change the spring.
2. Setting of damping force
9Change the rebound damping.
9Change the compression damping.
SPRING SPRINGI.D.
TYPE
RATE PART NUMBERMARK
(slits)
SOFT 0.398 1C3-23141-A0 I
STD 0.408 1C3-23141-N0 –
0.418 1C3-23141-C0 III
0.428 1C3-23141-D0 IIII
0.438 1C3-23141-E0 IIIII
STIFF 0.449 1C3-23141-F0 I-I
0.459 1C3-23141-G0 I-II
0.469 1C3-23141-H0 I-III
0.479 1C3-23141-J0 I-IIII
7-17
TUNSETTING
EC72C001
Choosing set length
1. Place a stand or block under the engine to
put the rear wheel above the floor, and mea-
sure the length abetween the rear wheel
axle center and the rear fender holding bolt.
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7-18
TUNSETTING
2. Remove the stand or block from the engine
and with a rider astride the seat, measure
the sunken length bbetween the rear wheel
axle center and the rear fender holding bolt.
3. Loosen the locknut 1and make adjustment
by turning the spring adjuster 2to achieve
the standard figure from the subtraction of
the length bfrom the length a.
Standard figure:
90~100 mm (3.5~3.9 in)
NOTE:
9If 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.
9If 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.
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7-19
TUNSETTING
EC72G020
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
9Set the soft spring for less rebound damp-
ing 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 preference.
2. Use of stiff spring
9Set the soft spring for more rebound damp-
ing to compensate for its greater spring
load. Run with the rebound damping
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.
cC
When using a rear cushion other than cur-
rently installed, use the one whose overall
length
a 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 a
of standard shock:
490 mm (19.29 in)
1C3-9-32-7B 4/28/06 10:39 AM Page 14

7-20
TUNSETTING
EC72Q011
Rear shock absorber setting parts
9Rear shock spring 1
[Equal-pitch titanium spring ]
[Equal-pitch steel spring ]
[Unequal-pitch steel spring ]
cC
Install the spring seat 2to the titanium
spring.
NOTE:
9The unequal-pitch spring is softer in initial char-
acteristic than the equal-pitch spring and is diffi-
cult to bottom out under full compression.
9The I.D. mark ais marked at the end of the
spring.
9Spring specification varies according to the
color and quantity of I.D. marks.
SPRING SPRINGI.D.SPRING
TYPE
RATE PART NUMBERMARKFREE
/Q’TYLENGTH
SOFT 4.3 5UN-22212-00Brown/1260
5.3 5UN-22212-50
Yellow/1260
5.5 5UN-22212-60 Pink/1 260
STIFF 5.7 5UN-22212-70 White/1 260
SPRING
SPRINGI.D.SPRING
TYPE RATE
PART NUMBERMARKFREE
(approx.)/Q’TYLENGTH
SOFT 4.5 5UN-22212-A0 Green/2 275
4.7 5UN-22212-B0 Red/2 275
4.9 5UN-22212-C0 Black/2 275
5.1 5UN-22212-D0 Blue/2 275
5.3 5UN-22212-E0
Yellow/2 275
5.5 5UN-22212-F0 Pink/2 275
STIFF 5.7 5UN-22212-G0
White/2 275
SPRING
TYPESPRING SPRING I.D.FREE
RATE PART NUMBER MARKLENGTH
(approx.)
SOFT 4.5 1C3-22212-00Green265
STD 4.7 1C3-22212-10Red265
STIFF4.9 1C3-22212-20 Black 265
5.1 1C3-22212-30 Blue 265
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7-21
TUNSETTING
9Extent of adjustment (spring length)
[Titanium spring]
[Steel spring]
SPRING FREE EXTENT OF
LENGTH ADJUSTMENT b
260mm (10.24in)240.5~258.5mm(9.47~10.18in)
275mm (10.83in)255.5~273.5mm(10.06~10.77in)
SPRING FREE EXTENT OF
LENGTH ADJUSTMENT b
One I.D. mark
245.5~263.5 mm
(9.67~10.37 in)
Approx. 265mmTwo I.D. marks
(10.43 in)251.5~269.5 mm
(9.90~10.61 in)
Three I.D. marks
243.0~261.0 mm
(9.57~10.28 in)
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7-22
TUNSETTING
EC72H010
Suspension setting
9Front fork
NOTE:
9If 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.
9Before any change, set the rear shock absorber sunken length to the standard figure 90~100 mm
(3.5~3.9 in).
Section
Symptom
JumpLarge
Medium Small Check Adjust
gap gap gap
Compression damping Turn adjuster counterclockwise (about 2 clicks)
Stiff over entire to decrease damping.
range111Oil amount Decrease oil amount by about 5~10 cm
3(0.2~0.4
Imp oz, 0.2~0.3 US oz).
Spring Replace with soft spring.
Outer tube Check for any bends, dents, and other notice-
Unsmooth Inner tube able scars, etc. If any, replace affected parts.
movement over 1111Slide metal Replace with a new one for extended use.
entire rangePiston metal Replace with a new one for extended use.
Under bracket tightening Retighten to specified torque.
torque
Poor initial Rebound damping Turn adjuster counterclockwise (about 2 clicks)
movement1to decrease damping.
Oil seal Apply grease in oil seal wall.
Compression damping Turn adjuster clockwise (about 2 clicks) to in-
Soft over entire crease damping.
range, bottoming 11Oil amount Increase oil amount by about 5~10 cm
3(0.2~0.4
outImp oz, 0.2~0.3 US oz).
Spring Replace with stiff spring.
Stiff toward stroke
1Oil amountDecrease oil amount by about 5 cm
3(0.2 Imp oz,
end0.2 US oz).
Soft toward stroke
1Oil amountIncrease oil amount by about 5 cm
3(0.2 Imp oz,
end, bottoming out 0.2 US oz).
Stiff initial
1111Compression dampingTurn adjuster counterclockwise (about 2 clicks)
movement to decrease damping.
Compression damping Turn adjuster clockwise (about 2 clicks) to in-
crease damping.
Low front, tending Rebound damping Turn adjuster counterclockwise (about 2 clicks)
to lower front 11to decrease damping.
postureBalance with rear end Set sunken length for 95~100 mm (3.7~3.9 in)
when one passenger is astride seat (lower rear
posture).
Oil amount Increase oil amount by about 5 cm
3(0.2 Imp oz,
0.2 US oz).
Compression damping Turn adjuster counterclockwise (about 2 clicks)
to decrease damping.
“Obtrusive” front, Balance with rear end Set sunken length for 90~95 mm (3.5~3.7 in)
tending to upper 11when one passenger is astride seat (upper rear
front postureposture).
Spring Replace with soft spring.
Oil amount Decrease oil amount by about 5~10 cm
3(0.2~0.4
Imp oz, 0.2~0.3 US oz).
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7-23
TUNSETTING
9Rear shock absorber
NOTE:
9If 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.
9Adjust the rebound damping in 2-click increments or decrements.
9Adjust the low compression damping in 1-click increments or decrements.
9Adjust the height compression damping in 1/6 turn increments or decrements.
Section
Symptom
JumpLarge
Medium Small Check Adjust
gap gap gap
Rebound damping Turn adjuster counterclockwise (about 2 clicks)
Stiff, tending to
11to decrease damping.
sink Spring set length Set sunken length for 90~100 mm (3.5~3.9 in)
when one passenger is astride seat.
Rebound damping Turn adjuster clockwise (about 2 clicks) to in-
Spongy and crease damping.
unstable11Low compression Turn adjuster clockwise (about 1 click) to in-
damping crease damping.
Spring Replace with stiff spring.
Heavy and Rebound damping Turn adjuster counterclockwise (about 2 clicks)
dragging11to decrease damping.
Spring Replace with soft spring.
Rebound damping Turn adjuster counterclockwise (about 2 clicks)
to decrease damping.
Low compression Turn adjuster clockwise (about 1 click) to in-
damping crease damping.
Poor road gripping1High compression Turn adjuster clockwise (about 1/6 turn) to
damping 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.
High compression Turn adjuster clockwise (about 1/6 turn) to in-
damping crease damping.
Bottoming out11Spring 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.
Rebound damping Turn adjuster clockwise (about 2 clicks) to in-
Bouncing11crease damping.
Spring Replace with soft spring.
High compression Turn adjuster counterclockwise (about 1/6
damping turn) to decrease damping.
Stiff travel11Spring 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.
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