ESP YAMAHA YZ450F 2004 Owner's Manual

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Examples of carburetor setting depending on symptom
This should be taken simply for an example. It is necessary to set the carburetor while checking
the operating conditions of the engine.
Symptom Setting Checking
At full throttle
Hard breathing
Shearing noise
Whitish spark plug
Lean mixtureIncrease main jet calibration no.
(Gradually)Discoloration of spark plug →
If tan color, it is in good condition.
If cannot be corrected:
Clogged float valve seat
Clogged fuel hose
Clogged fuel cock
Check that the accelerator pump oper-
ates smoothly.
At full throttle
Speed pick-up stops
Slow speed pick-up
Slow response
Sooty spark plug
Rich mixtureDecrease main jet calibration no.
(Gradually)Discoloration of spark plug →
If tan color, it is in good condition.
If cannot be corrected:
Clogged air cleaner
Fuel overflow from carburetor
Lean mixture Lower jet needle clip position.
(1 groove down)
The clip position is the jet needle
groove on which the clip is installed.
The positions are numbered from the
top.
Check that the accelerator pump oper-
ates smoothly (except for rich mixture
symptom). Rich mixture Raise jet needle clip position.
(1 groove up)
1/4 ~ 3/4 throttle
Hard breathing
Lack of speedLower jet needle clip position.
(1 groove down)
1/4 ~ 1/2 throttle
Slow speed pick-up
Poor accelerationRaise jet needle clip position.
(1 groove up)
Closed to 1/4 throttle
Hard breathing
Speed downUse jet needle with a smaller diameter. Slow-speed-circuit passage
Clogged → Clean.
Overflow from carburetor
Closed to 1/4 throttle
Poor accelerationUse jet needle with a larger diameter.
Raise jet needle clip position. (1 groove
up)
Poor response in the low to
intermediate speedsRaise jet needle clip position.
If this has no effect, lower the jet needle
clip position.
Poor response when throttle
is opened quicklyCheck overall settings.
Use main jet with a lower calibration no.
Raise jet needle clip position.
(1 groove up)
If these have no effect, use a main jet
with a higher calibration no. and lower
the jet needle clip position.Check air cleaner for fouling.
Check that the accelerator pump oper-
ates smoothly.
Jet needleClip
Groobe 7 Groobe 6
Groobe 5
Groobe 4
Groobe 3
Groobe 2
Groobe 1
Leaner
↑
(Standard)
↓
Richer
*
SETTING

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EC72P000
Front fork setting parts
Adjustment washer 1
Front fork spring 2
[Equal pitch spring]
* For EUROPE
[Unequal pitch spring]
NOTE:
The unequal pitch spring is softer in initial
characteristic than the equal pitch spring and
is difficult to bottom out under full compres-
sion.
The I.D. mark (slits) a is proved on the end
of the spring.TYPE (thickness) PART NUMBER
T = 2.3 mm (0.09 in) 5XE-23364-00
TYPESPRING
RATESPRING
PART NUMBERI.D.
MARK
(slits)
SOFT0.398
0.408
0.418
0.428
0.4385XE-23141-00
5XE-23141-10
5XE-23141-20
5XE-23141-30
5XE-23141-40I
II
III
IIII
IIIII
STD* 0.449 5XD-23141-M0–
STD 0.459 5XD-23141-L0–
STIFF0.469
0.4795XE-23141-70
5XE-23141-80I-III
I-IIII
TYPESPRING
RATE
(approx.)SPRING
PART NUMBERI.D.
MARK
(slits)
SOFT
STIFF0.398
0.418
0.438
0.459
0.4795XE-23141-A0
5XE-23141-B0
5XE-23141-C0
5XE-23141-D0
5XE-23141-E0V
V-I
V-II
V-III
V-IIII
SETTING

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EC72Q000
Rear shock absorber setting parts
Rear shock spring 1
[Equal pitch spring]
[Unequal pitch spring]
*For EUROPE
NOTE:
The unequal pitch spring is softer in initial
characteristic than the equal pitch spring and
is difficult to bottom out under full compres-
sion.
The I.D. color a is marked at the end of the
spring.
Extent of adjustment (spring length)
TYPESPRING
RATESPRING
PART NUMBERI.D.
COLOR/
POINTSPRING
FREE
LENGTH
SOFT4.3
4.5
4.7
4.9
5.15UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30
5UN-22212-40Brown/1
Green/1
Red/1
Black/1
Blue/1260
260
260
260
260
STD 5.3 5UN-22212-50 Yellow/1 260
STIFF5.5
5.75UN-22212-60
5UN-22212-70Pink/1
White/1260
260
TYPESPRING
RATE
(approx.)SPRING
PART NUMBERI.D.
COLOR/
POINTSPRING
FREE
LENGTH
SOFT4.5
4.7
4.9
5.15UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0Green/2
Red/2
Black/2
Blue/2275
275
275
275
*STD 5.3 5UN-22212-E0 Yellow/2 275
STIFF5.5
5.75UN-22212-F0
5UN-22212-G0Pink/2
White/2275
275
SPRING FREE
LENGTHEXTENT OF
ADJUSTMENT b
260 mm (10.24 in)240.5 ~ 258.5 mm
(9.47 ~ 10.18 in)
275 mm (10.83 in)255.5 ~ 273.5 mm
(10.06 ~ 10.77 in)

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Hinterradstoßdämpfer-Einstellteile
Hinterradstoßämpfer-Schraubenfeder 1
[Feder mit gleichmäßiger Gewindesteigung]
[Feder mit ungleichmäßiger Gewindesteigung]
* Nur EUROPA
HINWEIS:
Die Feder mit ungleichmäßiger Gewindestei-
gung ist in ihren anfänglichen Charakteristika
weicher als die Feder mit gleichmäßiger
Gewindesteigung und läßt sich nur schwer
unter vollem Druck herunterdrücken.
Die I.D. Farbe a ist am Ende der Feder mar-
kiert.
Einstellänge (Federlänge)
TYPFEDER-
KON-
STANTEFEDER-TEILE-
NUMMERI.D. MAR-
KIERUNG/
PUNKTUnge-
spannte
Feder-
länge
WEICH4,3
4,5
4,7
4,9
5,15UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30
5UN-22212-40Braun/1
Grün/1
Rot/1
Schwarz/1
Blau/1260
260
260
260
260
STD 5,3 5UN-22212-50 Gelb/1 260
HART5,5
5,75UN-22212-60
5UN-22212-70Rosa/1
Weiß/1260
260
TYPFEDER-
KON-
STANTE
(ca.)FEDER-TEILE-
NUMMERI.D. MAR-
KIERUNG/
PUNKTUnge-
spannte
Feder-
länge
WEICH4,5
4,7
4,9
5,15UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0Grün/2
Rot/2
Schwarz/2
Brau/2275
275
275
275
*STD 5,3 5UN-22212-E0 Gelb/2 275
HART5,5
5,75UN-22212-F0
5UN-22212-G0Rosa/2
Weiß/2275
275
UNGESPANNTE
FEDERLÄNGEEINSTELLÄNGE b
260 mm (10,24 in)240,5–258,5 mm
(9,47–10,18 in)
275 mm (10,83 in)255,5–273,5 mm
(10,06–10,77 in)
REGLAGE
EINSTELLUNG
Pièces de réglage de l’amortisseur arrière
Ressort d’amortisseur arrière 1
[Ressort à pas égal]
[Ressort à pas inégal]
* Pour l’Europe
N.B.:
Le ressort à pas inégal est plus souple suivant les
caractéristiques initiales que le ressort à pas égal
et atteind difficilement son niveau le plus bas
sous une compression totable.
La couleur a D.I. est indiquée à l’extrémité du
ressort.
Longueur de réglage (Longueur de ressort)
TypeConstante
du ressortNuméro de pièce de
ressortRepere
de d.i. /
pointLongueur
de ressort
MOU4,3
4,5
4,7
4,9
5,15UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30
5UN-22212-40Brun/1
Vert/1
Rouge/1
Noir/1
Bleu/1260
260
260
260
260
STD 5,3 5UN-22212-50 Jaune/1 260
DUR5,5
5,75UN-22212-60
5UN-22212-70Rose/1
Blanc/1260
260
TypeConstante
du ressort
(approx.)Numéro de pièce de
ressortRepere
de d.i. /
pointLongueur
de ressort
Mou4,5
4,7
4,9
5,15UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0Vert/2
Rouge/2
Noir/2
Bleu/2275
275
275
275
*STD 5,3 5UN-22212-E0 Jaune/2 275
DUR5,5
5,75UN-22212-F0
5UN-22212-G0Rose/2
Blanc/2275
275
LONGUEUR DE
RESSORT LIBRELONGUEUR DE
REGLAGE b
260 mm (10,24 in)240,5 à 258,5 mm
(9,47 à 10,18 in)
275 mm (10,83 in)255,5 à 273,5 mm
(10,06 à 10,77 in)
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