2005 YAMAHA YZ450F ESP

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TUN
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
operates 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 diame-
ter.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 nee-
dle clip position.
Poor response when throt-
tle 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
operates smoothly.
Jet needleClip
Groove 7 Groove 6
Groove 5
Groove 4
Groove 3
Groove 2
Groove 1
Leaner
↑
(Standard)
↓
Richer
*
SETTING

7 - 16
TUN
EC72P000
Front fork setting parts
Adjustment washer 1
Front fork spring 2
* For EUROPE
NOTE:
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) 1C3-23364-00
TYPESPRING
RATESPRING
PART NUMBERI.D.
MARK
(slits)
SOFT0.398
0.408
0.418
0.428
0.4381C3-23141-00
1C3-23141-10
1C3-23141-20
1C3-23141-30
1C3-23141-40I
II
III
IIII
IIIII
*STD 0.449 5XD-23141-P0–
STD 0.459 5XD-23141-N0–
STIFF0.469
0.4791C3-23141-70
1C3-23141-80I-III
I-IIII
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
Change the set length of the spring.
Change the spring.
2. Setting of damping force
Change the rebound damping.
Change the compression damping.
SETTING

7 - 19
TUNSETTING
EC72Q000
Rear shock absorber setting parts
Rear shock spring 1
[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. color a is marked at the end of the
spring.
TYPESPRING
RATESPRING
PART NUMBERI.D.
COLOR/
POINTSPRING
FREE
LENGTH
SOFT4.3
4.5
4.7
4.95UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30Brown/1
Green/1
Red/1
Black/1260
260
260
260
*STD 5.1 5UN-22212-40 Blue/1 260
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
SOFT
STIFF4.5
4.7
4.9
5.1
5.3
5.5
5.75UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0
5UN-22212-E0
5UN-22212-F0
5UN-22212-G0Green/2
Red/2
Black/2
Blue/2
Yellow/2
Pink/2
White/2275
275
275
275
275
275
275
Extent of adjustment (spring length)
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)

TUN
Einstellbare Federbein-Bauteile
Feder 1
[Gleichmäßige Steigung]
* EUROPE
[Ungleichmäßige Steigung]
HINWEIS:
Die Feder mit ungleichmäßiger Steigung ist
am Anfang des Federwegs weicher und
schlägt nicht leicht durch.
Die Kennzeichnung a ist am Federende
angebracht.
AUS-
FÜH-
RUNGFEDER-
RATEFEDER
TEILENUMMER
KENN-
ZEICH-
NUNG
(FARBE/
ANZAHL
PUNKTE)UNGE-
SPANNTE
LÄNGE
WEICH
4,3
4,5
4,7
4,95UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30Braun/1
Grün/1
Rot/1
Schwarz/1260
260
260
260
*STD 5,1 5UN-22212-40 Blau/1 260
STD 5,3 5UN-22212-50 Gelb/1 260
HART5,5
5,75UN-22212-60
5UN-22212-70Rosa/1
Weiß/1260
260
AUS-
FÜH-
RUNGFEDER-
RATE
(ca.)FEDER
TEILENUMMER
KENN-
ZEICH-
NUNG
(FARBE/
ANZAHL
PUNKTE)UNGE-
SPANNTE
LÄNGE
WEICH
HART4,5
4,7
4,9
5,1
5,3
5,5
5,75UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0
5UN-22212-E0
5UN-22212-F0
5UN-22212-G0Grün/2
Rot/2
Schwarz/2
Blau/2
Gelb/2
Rosa/2
Weiß/2275
275
275
275
275
275
275
Einstellbereich (Federlänge)
UNGESPANNTE
LÄNGEEINSTELLBEREICH
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 spires égales]
* EUROPE
[Ressort à spires inégales]
N.B.:
Le ressort à spires inégales est plus doux, dans
ses caractéristiques initiales, que le ressort à spi-
res égales, et est difficile à amener en fin de
course à pleine compression.
Le repère de couleur a se trouve à l’extrémité du
ressort.
TYPERAI-
DEUR
DU RES-
SORTRESSORT
REFERENCEREPERE
COU-
LEUR/
POINTLON-
GUEUR
LIBRE
DU RES-
SORT
MOU4,3
4,5
4,7
4,95UN-22212-00
5UN-22212-10
5UN-22212-20
5UN-22212-30Brun/1
Vert/1
Rouge/1
Noir/1260
260
260
260
*STD 5,1 5UN-22212-40 Bleu/1 260
STD 5,3 5UN-22212-50 Jaune/1 260
DUR5,5
5,75UN-22212-60
5UN-22212-70Rose/1
Blanc/1260
260
TYPERAI-
DEUR
DU RES-
SORT
(approx.)RESSORT
REFERENCEREPERE
COU-
LEUR/
POINTLON-
GUEUR
LIBRE
DU RES-
SORT
MOU
DUR4,5
4,7
4,9
5,1
5,3
5,5
5,75UN-22212-A0
5UN-22212-B0
5UN-22212-C0
5UN-22212-D0
5UN-22212-E0
5UN-22212-F0
5UN-22212-G0Vert/2
Rouge/2
Noir/2
Bleu/2
Jaune/2
Rose/2
Blanc/2275
275
275
275
275
275
275
Plage de réglage (longueur du ressort)
LONGUEUR LIBRE
DU RESSORTPLAGE 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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