2002 YAMAHA WR 400F tow

TUN
REGLAGE
EINSTELLUNG
AJUSTE
Einstellung der Leerlaufgemisch-
Regulierschraube
Der Kraftstoffgehalt des Luft-Kraft-
stoff-Gemisches bei 0–1/4 Gas kann
durch Drehen der Leerlaufgemisch-
Regulierschraube 1 eingestellt wer-
den. Die Leerlaufgemisch-Regulier-
schraube heraus- bzw. hineindrehen,
um bei niedrigen Drehzahlen ein fet-
teres bzw. mageres Gemisch zu
erhalten.
* Nicht USA
HINWEIS:
Wenn die Leerlaufdrehzahl
schwanken sollte, die Leerlaufge-
misch-Regulierschraube nur bis
maximal 1/2 Drehung in beide
Richtungen drehen.
Um den Kraftstoff-Fluß bei kleinem
Öffnungswinkel der Drosselklappe
zu optimieren, wurde die Leerlauf-
gemisch-Regulierschraube im
Werk für jeden Motor einzeln opti-
mal eingestellt. Ehe die Leerlauf-
gemisch-Regulierschraube neu
eingestellt wird, die Schraube ganz
hineindrehen und die Anzahl der
Umdrehungen zählen. Diese An-
zahl als werkseitige Voreinstel-
lung für das Herausdrehen der
Schraube aufzeichnen.
Wirkung der Einstellung der leer-
laufgemisch-Regulierschraube
ÅLeerlauf
ıVollgas
12 1/8 Drehungen heraus
21 1/8 Drehung heraus
31 5/8 Drehungen heraus
Standard-Posi-
tion der Leer-
laufgemisch-
Regulier-
schraubeWR426F: 1 5/8
*1-1/8
WR400F: 1 1/2
(Beispiel)
1/4 1/2 3/4
+5%
–5% AB
1
23
Réglage de la vis de ralenti
La richesse de l’émulsion air-essence à
une ouverture des gaz de 0 à 1/4 se règle
en tournant la vis de ralenti 1. Serrer la
vis de ralenti afin d’appauvrir et la des-
serrer afin d’enrichir l’émulsion à vites-
ses réduites.
* Excepté pour USA
N.B.:
Si le régime de ralenti n’est pas stable,
tourner la vis de ralenti d’un seul 1/2
tour dans un sens ou l’autre.
La vis de ralenti de chaque véhicule
est réglée individuellement en usine
afin de maximiser le flux de carburant
à petite ouverture des gaz. Avant de
régler la vis de ralenti, la visser tout à
fait et compter le nombre de tours
nécessaires. Noter ce chiffre, car il
s’agit du réglage d’usine.
Effets du réglage de la vis de ralenti
(référence)
ÅRalenti
ıComplètement ouvert
1Desserrer de 2-1/8 tours
2Desserrer de 1-1/8 tour
3Desserrer de 1-5/8 de tours
Position standard
de la vis de ralentiWR426F: 1-5/8
*1-1/8
WR400F: 1-1/2
(exemple)
1/4 1/2 3/4
+5%
–5% AB
1
23
7 - 5
Ajuste del tornillo piloto
Se puede ajustar la riqueza de la mezcla
de aire y combustible con el acelerador
desde completamente cerrado hasta
abierto en 1/4 girando el tornillo piloto
1. Si gira hacia dentro el tornillo piloto,
la mezcla se empobrecerá a velocidades
bajas y si lo gira hacia fuera, se enrique-
cerá dicha mezcla.
* Excepto para USA
NOTA:
Si fluctúa la velocidad de ralentí, gire
el tornillo piloto sólo 1/2 de vuelta en
cualquier dirección.
Para optimizar el flujo del combusti-
ble a una abertura menor del acelera-
dor, cada tornillo piloto de la máquina
ha sido ajustado individualmente en
fábrica. Antes de ajustar el tornillo
piloto, gírelo completamente hacia
dentro y cuente el número de vueltas.
Registre este número como el número
de vueltas hacia fuera del ajuste de
fábrica.
Efectos del ajuste del tornillo piloto
(referencia)
ÅRalentí
ıCompletamente abierto
12-1/8 de vueltas hacia fuera
21-1/8 de vueltas hacia fuera
31-5/8 de vueltas hacia fuera
Posición estándar
del tornillo pilotoWR426F: 1-5/8
*1-1/8
WR400F: 1-1/2
(ejemplo)
1/4 1/2 3/4
+5%
–5% AB
1
23

7 - 11
TUN
EC720000
CHASSIS
EC71P002
Selection of the secondary reduction ratio
(Sprocket)
Secondary
reduction =
ratio
reduction ratio>
It is generally said that the secondary gear
ratio should be reduced for a longer straight
portion of a speed course and should be
increased for a course with many corners.
Actually, however, as the speed depends on
the ground condition of the day of the race,
be sure to run through the circuit to set the
machine suitable for the entire course.
In actuality, it is very difficult to achieve set-
tings suitable for the entire course and some
settings may be sacrificed. Thus, the settings
should be matched to the portion of the
course that has the greatest effect on the
race result. In such a case, run through the
entire course while making notes of lap times
to find the best balance; then, determine the
secondary reduction ratio.
If a course has a long straight portion where
a machine can run at maximum speed, the
machine is generally set such that it can
develop its maximum revolutions toward the
end of the straight line, with care taken to
avoid the engine over-revving.
NOTE:
Riding technique varies from rider to rider and
the performance of a machine also vary from
machine to machine. Therefore, do not imitate
other rider’s settings from the beginning but
choose your own setting according to the level
of your riding technique.Standard secondary
reduction ratio50/14 (3.571)
SETTING
Number of driven sprocket teeth
Number of drive sprocket teeth

7 - 21
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 range

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

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

Rebound damping
Oil sealTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Apply grease in oil seal wall.
Soft over entire range,
bottoming out

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
Oil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
Soft toward stroke end,
bottoming out
Oil 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 posture

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

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).