lock YAMAHA YZ250LC 2004 Workshop Manual

6-4
IGNITION SYSTEMELEC
EC626003
IGNITION COIL INSPECTION
1. Inspect:
9Primary coil resistance
Out of specification Replace.
2. Inspect:
9Secondary coil resistance
Out of specification Replace.
NOTE:
9Remove the spark plug cap by turning it coun-
terclockwise and inspect.
9Install the spark plug cap by turning it clock-
wise until it is tight.
Tester (+) leadOrange lead 1
Tester (–) lead
Black lead 2
Tester (+) leadSpark plug lead 1
Tester (–) lead
Orange lead 2
Primary coil Tester selector
resistance position
0.20~0.30Ωat
Ω× 1
20°C (68°F)
Secondary coil Tester selector
resistance position
9.5~14.3kΩat
kΩ× 1
20°C (68°F)
5XF-9-30-6 4/21/03 2:13 PM Page 10

6-8
SYSTEME D’ELECTROVANNE
MAGNETVENTILSYSTEM
SISTEMA ELETTROVALVOLA
ELEC
INSPEKTION DES ANSCHLUSSES
DER KUPPLUNGEN UND KABEL
1. Kontrollieren:
9Anschluß deren Kupplungen
und Kabel
Rost/Staub/Lockerheit/Kurz-
schlußReparieren oder
erneuern.
BETRIEBSABLAUF DES
MAGNETVENTILS
1. Stecker des Magnetventils lösen.
2. 12V-Batterie am Magnetventil-
stecker anschließen.
3. Prüfen:
9Magnetventil 1
Kein Klickgeräusch beim
Anschließen der Batterie 
Erneuern.
ÜBERPRÜFUNG DER
MAGNETVENTILSPULE
1. Prüfen:
9Widerstand der Magnetventil-
spule
Abweichung von Spezifikation
Erneuern.
VERIFICATION DE CONNEXION
DES COUPLEURS ET FILS
1. Contrôler:
9Connexion des coupleurs et fils
Rouille/poussière/desserré/court
-circuit

Réparer ou changer.
FONCTIONNEMENT DE
L’ÉLECTROVANNE
1. Déconnectez le raccord de l’élec-
trovanne.
2. Branchez une batterie de 12 V au
raccord de l’électrovanne.
3. Examiner:
9Electrovanne 1
Pas de clic lors de la connexion
de la batterie
Changer.
INSPECTION DE LA BOBINE
DE L’ÉLECTROVANNE
1. Examiner:
9Résistance de la bobine d’élec-
trovanne
Hors spécification Changer.
IC624000
ISPEZIONE DEL
COLLEGAMENTO DI
ACCOPPIATORI E CONDUTTORI
1. Controllare:
9Collegamento di accoppiatori e
conduttori
Ruggine/Polvere/Allentamen-
to/Cortocircuito Ripararli o
sostituirli.
IC652040
FUNZIONAMENTO
DELL’ ELETTROVALVOLA
1. Scollegare l’accoppiatore dell’elet-
trovalvola.
2. Collegare la batteria 12V
all’accoppiatore dell’elettrovalvo-
la.
3. Ispezionare:
9Elettrovalvola 1
Nessun clic quando si collega la
batteria
Sostituire.
IC653002
CONTROLLO DELLA BOBINA
DELL’ELETTROVALVOLA
1. Ispezionare:
9Resistenza della bobina
dell’elettrovalvola
Fouori specificaSostituirla.
Conduttore (+) del tester 
Conduttore Rosso 1
Conduttore (–) del tester 
Conduttore Rosso 2
Fil (+) de testeur
Fil rouge1
Fil (–) de testeur
Fil rouge2
Positives (+) Kabel des Prüfgerätes
Rot Kabel 1
Negatives (–) Kabel des Prüfgeräte
Rot Kabel 2
Résistance Position de
du sélecteur de
solénoïde testeur
22,8~27,8ΩàΩ×10
20°C (68°F)
Magnet- Position des spulenwider- Wahlschaltersstandam Prüfgerät
22,8~27,8ΩbeiΩ× 1020°C (68°F)
ResistenzaPosizione del
solenoideselettore del
tester
22,8~27,8Ωa
Ω× 10
20°C (68°F)
Fil de batterie (+) 
Fil rouge 1
Fil de batterie (–) 
Fil rouge 2Batterie (+)-Leitung 
Rot Kabel 1
Batterie (–)-Leitung 
Rot Kabel 2
Conduttore (+) della batteria 
Conduttore Rosso 1
Conduttore (–) della batteria 
Conduttore Rosso 2
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6-10
SYSTEME TPS (CAPTEUR DE POSITION DU PAPILLON)
TPS-SYSTEM (TPS = DROSSELSTELLUNGSSENSOR)
SISTEMA TPS (SENSORE DI POSIZIONE DELL’ACCELERATORE)ELEC
VERIFICATION DE CONNEXION
DES COUPLEURS ET FILS
1. Contrôler:
9Connexion des coupleurs et fils
Rouille/poussière/desserré/court
-circuit

Réparer ou changer.
INSPEKTION DES ANSCHLUSSES
DER KUPPLUNGEN UND KABEL
1. Kontrollieren:
9Anschluß deren Kupplungen
und Kabel
Rost/Staub/Lockerheit/Kurz-
schlußReparieren oder
erneuern.
IC624000
ISPEZIONE DEL
COLLEGAMENTO DI
ACCOPPIATORI E CONDUTTORI
1. Controllare:
9Collegamento di accoppiatori e
conduttori
Ruggine/Polvere/Allentamen-
to/Cortocircuito Ripararli o
sostituirli.
INSPECTION DE LA BOBINE DU
TPS
1. Déposer:
9Carburateur
9Haut de chambre de mélange
Se reporter à la section “CAR-
BURATEUR ET SOUPAPE
FLEXIBLE”.
TPS-SPULENINSPEKTION
1. Ausbauen:
9Vergaser
9Mischkammer-Oberteil
Siehe Abschnitt „VERGASER
UND ZUNGENVENTIL“.IC692000
ISPEZIONE DELLA BOBINA DEL
TPS
1. Togliere:
9Carburatore
9Parte superiore del diffusore
Consultare la sezione “CARBU-
RATORE E VALVOLA A LA
MELLA”.
2. Examiner:
9Résistance de la bobine du TPS
Hors spécification
Changer.
2. Prüfen:
9TPS-Spulenwiderstand
Abweichung von Spezifikation
Erneuern.2. Ispezionare:
9Resistenza della bobina del TPS
Fuori specifica Sostituirla.
Resistenza
Posizione del della bobina selettore del
del TPS tester
4~6kΩa
kΩ× 1
20°C (68°F)
Conduttore (+) del tester 
Conduttore Blu 1
Conduttore (–) del tester 
Conduttore nero 2
Résistance Position de
de la bobine sélecteur de
du TPS testeur
4~6kΩà
kΩ×1
20°C (68°F)
Fil (+) de testeurFil bleu 1
Fil (–) de testeurFil noir 2Positives (+) Kabel des Prüfgerätes
Blau Kabel 1
Negatives (–) Kabel des Prüfgerätes
Schwarz Kabel 2
TPS- Position des
Spulen-
Wahlschalterswiderstand am Prüfgerät
4~6kΩbei
kΩ× 1
20°C (68°F)
REMARQUES CONCERNANT LA
MANIPULATION
fF
Ne pas desserrer les vis du fil du cap-
teur de position du papillon (TPS),
sauf lors du remplacement du cap-
teur de position du papillon (TPS) à
la suite d’une défaillance, car cela va
provoquer une altération des perfor-
mances du moteur.
HANDHABUNGSHINWEISE
dD
Schrauben des TPS-Leitungskabels
(Drosselstellungssensor) nur dann
lösen wenn das TPS-Leitungskabel
(Drosselstellungssensor) wegen
einer Störung ausgewechselt wer-
den muß, denn dadurch wird ein
Abfall bei der Motorleistung
bewirkt.
IC69A000
NOTA PER IL MANEGGIO
iI
Non allentare le viti [conduttore TPS
(sensore di posizione gas)] se non per
cambiare il conduttore TPS (sensore
di posizione gas) qualora si guasti per
evitare di compromettere le presta-
zioni del motore.
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7-15
SETTINGTUN
A
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.
*For EUROPE
åAir spring characteristics in relation to oil level
change
∫Load
çStroke
1Max. oil level
2Standard oil level
3Min. oil level
Standard oil level:
123 mm (4.84 in)
*125 mm (4.92 in)
Extent of adjustment:
105~135 mm (4.13~5.31 in)
From top of outer tube with
inner tube and damper rod fully
compressed without spring.
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7-19
SETTINGTUN
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)
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7-19
REGLAGE
EINSTELLUNG
REGISTRAZIONETUN
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
SETTINGTUN
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
SETTINGTUN
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.
Spongy and Rebound damping Turn adjuster clockwise (about 2 clicks) to in-
unstablecrease damping.
11Low 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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