2001 YAMAHA YZ426F lock

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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
l
Change the set length of the spring.
l
Change the spring.
2. Setting of damping force
l
Change the rebound damping.
l
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
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 holding 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

TUN
Hinterradaufhängung einstellen
Die Einstellung der Hinterradaufhängung soll
entsprechend dem Gefühl des Fahrers, nach
einer Testfahrt und entsprechend dem Zu-
stand der Strecke vorgenommen werden.
Die Einstellung der Hinterradaufhängung um-
faßt folgende beide Faktoren:
1. Einstellung der Federvorspannung
lFedereinbaulänge ändern
lFeder ändern
2. Einstellung der Dämpfungskraft
lZugstufendämpfung einstellen
lDruckstufendämpfung einstellen
Federeinbaulänge wählen
1. Das Motorrad am Motor aufbocken, um
das Hinterrad anzuheben, und den Ab-
stand a zwischen der Hinterachsmitte
und der Hinterrad-Abdeckungs-Schraube
messen.
2. Das Motor herablassen und bei aufsit-
zendem Fahrer den Abstand b zwischen
der Hinterachsmitte und der Hinterrad-
Abdeckungs-Schraube messen.
3. Die Sicherungsmutter 1 lockern und die
Einstellmutter 2 verdrehen, um die Stan-
dard-Federeinbaulänge a-b zu erhal-
ten.
Standard-Federeinbaulänge
90–100 mm
REGLAGE
EINSTELLUNG
Réglage de la suspension arrière
Effectuer le réglage de la suspension arrière en
fonction de la sensation lors de la conduite ainsi
que des conditions de route.
Les deux réglages de la suspension arrière sont les
suivants:
1. Réglage de la précharge du ressort
lRégler la longueur du ressort.
lChanger de type de ressort.
2. Réglage de la force d’amortissement
lRégler la force de rebond.
lRégler la force de compression.
Choix de la longueur de ressort
1. Placer un support ou un bloc sous le moteur
pour surélever la roue arrière et mesurer la
longueur a entre le centre de l’axe de roue
arrière et le boulon de fixation du garde-boue
arrière.
2. Retirer le support ou le bloc et mesurer, avec
une personne assise correctement sur la selle,
la longueur b entre le centre de l’axe de roue
arrière et le boulon de fixation du garde-boue
arrière.
3. Desserrer le contre-écrou 1 et effectuer le
réglage en tournant le dispositif de réglage 2
de sorte à régler à la valeur standard, obtenue
en soustrayant la longueur b de la longueur
a.
Valeur standard:
90 à 100 mm (3,5 à 3,9 in)
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SETTING
EC72H002
Suspension setting
l
Front fork
NOTE:

l
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.
l
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
gap
Medium
gap
Small
gap
Stiff over entire range
CCC
Compression damping
Oil level (oil amount)
SpringTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Replace with soft spring.
Unsmooth movement
over entire range
CCCC
Outer tube
Inner tube
Under bracket tightening
torqueCheck for any bends, dents, and other noticeable
scars, etc. If any, replace affected parts.
Retighten to specified torque.
Poor initial
movement
C
Rebound damping
Oil sealTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Apply grease in oil seal wall.
Soft over entire range,
bottoming out
CC
Compression damping
Oil level (oil amount)
SpringTurn adjuster clockwise (about 2 clicks) to increase
damping.
Increase oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Replace with stiff spring.
Stiff toward stroke end
C
Oil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
Soft toward stroke end,
bottoming out
C
Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
Stiff initial movement
CCCC
Compression dampingTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low front, tending to
lower front posture
CC
Compression damping
Rebound damping
Balance with rear end
Oil level (oil amount)Turn adjuster clockwise (about 2 clicks) to increase
damping.
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in) when
one passenger is astride seat (lower rear posture).
Increase oil level by about 5 mm (0.2 in).
“Obtrusive” front, tend-
ing to upper front pos-
ture
CC
Compression damping
Balance with rear end
Spring
Oil lever (oil amount)Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Set sunken length for 90 ~ 95 mm (3.5 ~ 3.7 in) when
one passenger is astride seat (upper rear posture).
Replace with soft spring.
Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).

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SETTING
l
Rear shock absorber
NOTE:

l
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.
l
Adjust the rebound damping in 2-click increments or decrements.
l
Adjust the low compression damping in 1-click increments or decrements.
l
Adjust the high compression damping in 1/6 turn increments or decrements.
SymptomSection
Check Adjust
JumpLarge
gap
Medium
gap
Small
gap
Stiff, tending to sink
CC
Rebound damping
Spring set lengthTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in) when
one passenger is astride seat.
Spongy and unstable
CC
Rebound damping
Low compression damping
SpringTurn adjuster clockwise (about 2 clicks) to increase
damping.
Turn adjuster clockwise (about 1 click) to increase
damping.
Replace with stiff spring.
Heavy and dragging
CC
Rebound damping
SpringTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Replace with soft spring.
Poor road gripping
C
Rebound damping
Low compression damping
High compression damp-
ing
Spring set length
SpringTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Turn adjuster clockwise (about 1 clicks) to increase
damping.
Turn adjuster clockwise (about 1/6 clicks) to increase
damping.
Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in) when
one passenger is astride seat.
Replace with soft spring.
Bottoming out
CC
High compression damp-
ing
Spring set length
SpringTurn adjuster clockwise (about 1/6 turn) to increase
damping.
Set sunken length for 90 ~ 100 mm (3.5 ~ 3.9 in) when
one passenger in astride seat.
Replace with stiff spring.
Bouncing
CC
Rebound damping
SpringTurn adjuster clockwise (about 2 clicks) to increase
damping.
Replace with soft spring.
Stiff travel
CC
High compression damp-
ing
Spring set length
SpringTurn adjuster counterclockwise (about 1/6 turn) to
decrease damping.
Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in) when
one passenger is astride seat.
Replace with soft spring.