lock YAMAHA YZ125LC 2002 Workshop Manual

5-50
CHASSTEERING
4. Install:
9Plain washer 1
9Ring nut 2
Tighten the ring nut using the ring nut
wrench 3.
Refer to “STEERING HEAD INSPECTION
AND ADJUSTMENT” section in the CHAP-
TER 3.
5. Check the steering shaft by turning it lock to
lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
6. Install:
9Plain washer 1
7. Install:
9Front fork 1
9Handle crown 2
NOTE:
9Temporarily tighten the pinch bolts (under
bracket).
9Do not tighten the pinch bolts (handle crown) yet.
8. Install:
9Plain washer 1
9Steering shaft nut 2
7 Nm (0.7 m•kg, 5.1 ft•lb)
145 Nm (14.5 m•kg, 105 ft•lb)
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5-59
CHASREAR SHOCK ABSORBER
Extent of removal Order Part name Q’ty Remarks
REAR SHOCK ABSORBER
REMOVAL
Preparation forHold the machine by placing the
removalsuitable stand under the engine.
SeatRefer to “SEAT, FUEL TANK AND
SIDE COVERS” section.
SilencerRefer to “EXHAUST PIPE AND
SILENCER” section.
1 Clamp (air cleaner joint) 1 Loosen the screw (air cleaner joint).
2 Rear frame 1
3
Bolt (rear shock absorber-relay arm)1 Hold the swingarm.
4 Bolt (rear shock absorber-frame) 1
5 Rear shock absorber 1
6 Locknut 1
7 Adjuster 1
8 Spring guide (lower) 1
9 Spring guide (upper) 1
10 Spring (rear shock absorber) 1
11 Bearing 2 Refer to “REMOVAL POINTS”.
2
w
Support the machine securely so there is no dan-
ger of it falling over.
Extent of removal:1Rear shock absorber removal 2Rear shock absorber disassembly
1
56 Nm (5.6 m•kg, 40 ft•lb)
53 Nm (5.3 m•kg, 38 ft•lb)
29 Nm (2.9 m•kg, 21 ft•lb)
EC580000
REAR SHOCK ABSORBER
5NY-9-30-5D 5/23/01 9:14 PM Page 16

5-63
CHASREAR SHOCK ABSORBER
EC5852B4
Rear shock absorber
1. Install:
9Dust seal 1
9O-ring 2
9Collar 3
NOTE:
9Apply the molybdenum disulfide grease on the
bearing.
9Apply the lithium soap base grease on the dust
seals, O-rings and collars.
2. Install:
9Bush 1
9Collar 2
9Dust seal 3
NOTE:
9Apply the molybdenum disulfide grease on the
bearing.
9Apply the lithium soap base grease on the
bush, collars and dust seals.
9Install the dust seals with their lips facing out-
ward.
3. Adjust:
9Spring length (installed) a
*For EUROPE
NOTE:
The length of the spring (installed) changes 1.5
mm (0.06 in) per turn of the adjuster.
cC
Never attempt to turn the adjuster beyond
the maximum or minimum setting.
4. Tighten:
9Locknut 1
Spring length (installed) a
a
:
Standard
length
248 mm (9.76 in)
*262 mm (10.31 in)Extent of
adjustment
240.5~258.5 mm
(9.47~10.18 in)
*255.5~273.5 mm
(10.06~10.77 in)
5NY-9-30-5D 5/23/01 9:15 PM Page 24

6-3
ELEC
SYSTEME D’ALLUMAGE
ZÜNDANLAGE
SISTEMA DI ACCENSIONE
TEST DER ZÜNDFUNKENSTRECKE
1. Den Zündkerzenstecker von der
Zündkerze abtrennen.
2. Den dynamischen Zündfunken-
prüfer 1(Zündungs-Prüfgerät
2) gemäß Abbildung ansch-
ließen.
9Zündkerzenstecker 3
9Zündkerze 4
AFür USA und CDN
BAußer USA und CDN
3. Den Motor mit Hilfe des Kickstar-
ters durchdrehen.
4. Die Zündfunkenstrecke kontrollie-
ren.
5. Den Motor anlassen und die
Zündfunkenstrecke vergrößern,
bis es zu Fehlzündungen kommt.
(nur für USA und CDN)
INSPEKTION DES ANSCHLUSSES
DER KUPPLUNGEN UND KABEL
1. Kontrollieren:
9Anschluß deren Kupplungen
und Kabel
Rost/Staub/Lockerheit/Kurz-
schlußReparieren oder
erneuern.
INSPEKTION DES MOTORSTOPP-
KNOPFES „ENGINE STOP“
1. Prüfen:
9Kontakt des Motorstoppknop-
fes „ENGINE STOP“
Kein Stromdurchgang, wenn gedrückt
Erneuern.
Stromdurchgang, wenn freigelassen
Erneuern.ESSAI DE L’INTERVALLE
D’ETINCELLEMENT
D’ ALLUMAGE
1. Déconnecter le capuchon de bou-
gie de la bougie.
2. Connecter le testeur dynamique
d’étincelle 1(testeur d’allumage
2) comme indiqué.
9Capuchon de bougie 3
9Bougie 4
A Pour USA et CDN
BExcepté pour USA et CDN
3. Actionner la pédale de kick.
4. Contrôler l’écartement d’étincelle
d’allumage.
5. Démarrer le moteur et augmenter
l’intervalle d’étincellement jusqu’à
ce qu’un raté se produise. (unique-
ment USA et CDN)
VERIFICATION DE CONNEXION
DES COUPLEURS ET FILS
1. Contrôler:
9Connexion des coupleurs et fils
Rouille/poussière/desserré/court
-circuit→
Réparer ou changer.
VERIFICATION DU BOUTON
D’ARRET DU MOTEUR “ENGINE
STOP”.
1. Examiner:
9Conductibilité du bouton d’arrêt
du moteur “ENGINE STOP”
Pas de continuité lorsqu’enfoncé 
Changer.
Continuité lorsque relâché  Changer.
IC622001
TEST DELLA DISTANZA TRA
GLI ELETTRODI
1. Scollegare la calotta della candela
dalla candela.
2. Collegare il tester dinamico delle
scintille 1(apparecchio per il
controllo dell’accensione 2) come
illustrato.
9Calotta della candela 3
9Candela 4
APer USA e CDN
BTranne che per USA e CDN
3. Azionare la pedivella della messa
in moto.
4. Controllare la distanza tra gli elet-
trodi dell’accensione.
5. Avviare il motore e aumentare la
distanza tra gli elettrodi finché non
si verifica uno scatto a vuoto. (sol-
tanto per USA e CDN)
IC624000
ISPEZIONE DEL
COLLEGAMENTO DI
ACCOPPIATORI E CONDUTTORI
1. Controllare:
9Collegamento di accoppiatori e
conduttori
Ruggine/Polvere/Allentamen-
to/Cortocircuito Ripararli o
sostituirli.
IC625002
ISPEZIONE DEL PULSANTE
“ARRESTO MOTORE”
1. Ispezionare:
9Comportamento del pulsante
“ARRESTO MOTORE”
Assenza di continuità mentre è premuto
Sostituirlo.
Continuità mentre viene rilasciato 
Sostituirlo.B/W B
Posizione12del seletto
re del tester
PREM-
11UTO
RILAS-Ω× ×

1
CIATO
Conduttore (+) del tester 
Conduttore Nero/Bianco 1
Conduttore (–) del tester 
Conduttore Nero 2
Distanza minima tra gli
elettrodi:
6,0 mm (0,24 in)
Ecartement d’étincelle
minimum:
6,0 mm (0,24 in)
Fil (+) de testeur 
Fil noir/blanc 1
Fil (–) de testeur 
Fil noir 2
B/W BPosition de12sélecteur du
testeur
ENFO-
11NCE
RELA-Ω× ×

1
CHE
Min. Zündfunkenstrecke:
6,0 mm (0,24 in)
Positives (+) Kabel des Prüfgerätes
Schwarz/Weiß Kabel 1
Negatives (–) Kabel des Prüfgerätes
Schwarz Kabel 2
B/W BPosition des12Wahlschaltersam Prüfgerät
GEDR-11ÜCKT
FREIGE-Ω×
×

1
LASSEN
5NY-9-30-6 5/23/01 9:17 PM Page 9

7-15
TUNSETTING
EC722011
Front fork setting
The front fork setting should be made depending
on the rider’s feeling of an actual run and the cir-
cuit conditions.
The front fork setting includes the following three
factors:
1. Setting of air spring characteristics
9Change the fork oil level.
2. Setting of spring preload
9Change the spring.
9Install the adjustment washer.
3. Setting of damping force
9Change the compression damping.
9Change the rebound damping.
The spring acts on the load and the damp-
ing force acts on the cushion travel speed.
EC723001
Change in level and characteristics of fork oil
Damping characteristic near the final stroke can
be changed by changing the fork oil amount.
cC
Adjust the oil level in 5 mm (0.2 in) incre-
ments or decrements. Too low oil level
causes the front fork to produce a noise at
full rebound or the rider to feel some pres-
sure on his hands or body. Alternatively,
too high oil level will develop unexpectedly
early oil lock with the consequent shorter
front fork travel and deteriorated perfor-
mance an characteristics. Therefore, adjust
the front fork within the specified range.
åAir spring characteristics in relation to oil level
change
∫Load
çStroke
1Max. oil level
2Standard oil level
3Min. oil level
Standard oil level:
135 mm (5.31 in)
Extent of adjustment:
80~150 mm (3.15~5.91 in)
From top of outer tube with
inner tube and damper rod fully
compressed without spring.
A
5NY-9-30-7B 5/23/01 9:22 PM Page 6

7-19
TUNSETTING
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.
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.
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)
5NY-9-30-7B 5/23/01 9:22 PM Page 14

7-19
TUN
REGLAGE
EINSTELLUNG
REGISTRAZIONE
Einstellung der Hinterradfederung
Die Einstellung der Hinterradfederung
soll entsprechend dem Gefühl des
Fahrers nach einer Testfahrt und den
Bedingungen der Strecke vorgenom-
men werden.
Die Einstellung der Hinterradfederung
beinhaltet die folgenden beiden Fakto-
ren:
1. Einstellung der Federvorspan-
nung
9Änderung der Federlänge
9Umstellung der Feder
2. Einstellung der Dämpfungskraft
9Änderung der Ausfederdämp-
fung
9Änderung der Federfeder-
dämpfungRéglage 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
9Régler la longueur du ressort.
9Changer de type de ressort.
2. Réglage de la force d’amortisse-
ment
9Régler la force de rebond.
9Régler 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 lon-
gueur bentre le centre de l’axe de
roue arrière et le boulon de fixa-
tion du garde-boue arrière.
3. Desserrer le contre-écrou 1et
effectuer le réglage en tournant le
dispositif de réglage 2desorte à
régler à la valeur standard obtenue
en soustrayant la longueur bde la
longueur a.
Wahl der Einstellänge
1. Einen Ständer oder Block unter
den Motor stellen, um das Hinter-
rad anzuheben, und den Abstand
azwischen der Hinterradachs-
mitte und der Hinterradkotflügel-
Halteschraube messen.
2. Den Ständer oder Block vom
Motor entfernen und bei aufsit-
zendem Fahrer die eingetauchte
Tiefe bzwischen der Hinterrad-
achsmitte und der Hinterradkot-
flügel-Halteschraube messen.
3. Die Gegenmutter 1lösen, und
die Einstellung durch Drehen des
Federeinstellers 2vornehmen,
um den Standardwert von der
Subtraktion der Länge bvon der
Länge azu erhalten.IC72C001
Scelta della lunghezza registrata
1. Collocare sotto il motore un sup-
porto o un blocco per rialzare dal
suolo la parte superiore e misurare
la lunghezza afra il centro
dell’asse della ruota posteriore e il
bullone di tenuta del parafango
posteriore.
2. Togliere dal motore il supporto o il
blocco e, con un guidatore a caval-
cioni della sella, misurare la lun-
ghezza abbassata bfra il centro
dell’asse della ruota posteriore e il
bullone di tenuta del parafango
posteriore.
3. Allentare il controdado 1ed
effettuare la regolazione ruotando
il regolatore della molla 2per
ottenere la cifra normale sottraen-
do la lunghezza bdalla lunghezza
a.
IC72B000
Registrazione della sospensione
posteriore
La registrazione della sospensione
posteriore dovrebbe essere effettuata in
base alla sensazione che il guidatore ha
di una corsa effettiva e alle condizioni
del circuito.
La registrazione della sospensione poste-
riore comprende i seguenti due fattori:
1. Registrazione del precarico della
molla
9Cambiare la lunghezza registra-
ta della molla.
9Cambiare la molla.
2. Registrazione della forza di smor-
zamento
9Cambiare lo smorzamento
dell’estensione.
9Cambiare lo smorzamento della
compressione.
Valeur standard:
90~100 mm (3,5~3,9 in)
Standardwert:
90~100 mm (3,5~3,9 in)Cifra normale:
90~100 mm (3,5~3,9 in)
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7-23
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 level (oil amount) Decrease oil level by about 5~10 mm (0.2~0.4
in).
Spring Replace with soft spring.
Unsmooth Outer tube Check for any bends, dents, and other notice-
movement over 1111Inner tube able scars, etc. If any, replace affected parts.
entire range
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 level (oil amount) Increase oil level by about 5~10 mm (0.2~0.4
outin).
Spring Replace with stiff spring.
Stiff toward stroke
1Oil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
end
Soft toward stroke
1Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
end, bottoming out
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 level (oil amount) Increase oil level by about 5 mm (0.2 in).
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 lever (oil amount) Decrease oil level by about 5~10 mm (0.2~0.4
in).
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7-24
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 hight 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.
5NY-9-30-7B 5/23/01 9:22 PM Page 23