2003 YAMAHA WR 450F torque

SPEC

2 - 19
MAINTENANCE SPECIFICATIONS
NOTE:

Tighten the rotor nut to 65 Nm (6.5 m·kg, 47 ft·lb), loosen and retighten the rotor nut to 65 Nm
(6.5 m·kg, 47 ft·lb). Starter relay:
Model/manufacturer 2768090-A/JIDECO ----
Amperage rating 180 A ----
Coil winding resistance 4.2 ~ 4.6
Ω
at 20 ˚C (68 ˚F) ----
Starting circuit cut-off relay:
Model/manufacturer ACM33221 M06/MATSUSHITA ----
Coil winding resistance 75.69 ~ 92.51
Ω
at 20 ˚C (68 ˚F) ----
Fuse (amperage
×
quantity):
Main fuse 10 A
×
1 ----
Reserve fuse 10 A
×
1 ----
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Stator M5
×
0.8 2 7 0.7 5.1
Holder (AC magneto lead) M5
×
0.8 2 7 0.7 5.1
Rotor M12
×
1.25 1 Refer to NOTE.
Neutral switch M5
×
0.8 2 4 0.4 2.9
Starter motor M6
×
1.0 2 10 1.0 7.2
Starter relay terminal M6
×
1.0 2 4 0.4 2.9 Item Standard Limit

2 - 20
SPEC

GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3

meter
10
-2

meterLength
Length
kg kilogram 10
3

gram Weight
N Newton 1 kg
×
m/sec
2

Force
Nm
m • kgNewton meter
Meter kilogramN
×
m
m
×
kgTorque
Torque
Pa Pascal N/m
2

Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3

Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed

3 - 46
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Tighten the ring nut 3 using ring nut
wrench 4.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m • kg, 27 ft • lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
7 Nm (0.7 m • kg, 5.1 ft • lb)
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.
Install the plain washer 5, handle crown
6, plain washer 7, steering shaft nut 8,
steering shaft cap 9, handlebar 0, han-
dlebar holder A and headlight B.
NOTE:
The handlebar holder should be installed
with the punched mark a forward.
Insert the end of the fuel breather hose C
into the hole in the steering shaft cap.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder, and then tighten
the bolts on the rear side.
T R..
Steering shaft nut:
145 Nm (14.5 m • kg, 105 ft • lb)
Handlebar holder:
28 Nm (2.8 m • kg, 20 ft • lb)
Pinch bolt (handle crown):
23 Nm (2.3 m • kg, 17 ft • lb)
Headlight (left and right):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Headlight (lower):
7 Nm (0.7 m • kg, 5.1 ft • lb)

ENG
4 - 14
CARBURATEUR
VERGASER
CARBURADOR
Beschleunigungspumpe
1. Kontrollieren:
Membran (Beschleuni-
gungspumpe) 1
Feder 2
Deckel 3
O-Ring 4
Druckstange 5
Rißbildung (Membran)/
Beschädigung → Erneuern.
Verunreinigung → Reinigen.
2. Inspizieren:
Drosselwelle 1
Feder 2
Hebel 1 3
Feder 1 4
Hebel 2 5
Feder 2 6
Schmutz → Säubern.
Luftabschaltventil
1. Kontrollieren:
Membran (Luftabschaltven-
til) 1
Feder (Luftabschaltventil) 2
Luftabschaltventil-Deckel 3
O-Ring 4
Rißbildung (Membran)/
Beschädigung → Erneuern.
ZUSAMMENBAU UND MONTAGE
Vergaser
1. Montieren:
Kaltstarter-Tauchkolben 1
2. Montieren:
Leerlaufluftdüse 1 Pompe d’accélérateur
1. Contrôler:
Diaphragme (pompe d’accélé-
rateur) 1
Ressort 2
Couvercle 3
Joint torque 4
Tige de poussée 5
Déchirure (diaphragme)/
endommagement → Rempla-
cer.
Encrassement → Nettoyer.
2. Inspecter:
Axe de papillon 1
Ressort 2
Levier 1 3
Ressort 1 4
Levier 2 5
Ressort 2 6
Sale → Nettoyer.
Clapet de coupure d’air
1. Inspecter:
Membrane (clapet de coupure
d’air) 1
Ressort (clapet de coupure
d’air) 2
Couvercle de clapet de coupure
d’air 3
Joint torique 4
Déchirures (membrane)/
endommagement → Rempla-
cer.
ASSEMBLAGE ET MONTAGE
Carburateur
1. Monter:
Plongeur de démarrage à froid
1
2. Monter:
Gicleur d’air de ralenti 1 Bomba de aceleración
1. Inspeccionar:
Diafragma (bomba de acelera-
ción) 1
Muelle 2
Cubierta 3
Junta tórica 4
Varilla de empuje 5
Desgarraduras (diafragma)/
daños → Reemplazar.
Suciedad → Limpiar.
2. Inspeccionar:
Eje del acelerador 1
Resorte 2
Palanca 1 3
Resorte 1 4
Palanca 2 5
Resorte 2 6
Sucio → Limpiar.
Válvula de corte de aire
1. Inspeccionar:
Diafragma (válvula de corte de
aire) 1
Muelle (válvula de corte de
aire) 2
Cubierta de la válvula de corte
de aire 3
Junta tórica 4
Desgarraduras (diafragma)/
daños → Reemplazar.
MONTAJE E INSTALACIÓN
Carburador
1. Instalar:
Empujador de arranque en frío
1
2. Instalar:
Surtidor de aire piloto 1

4 - 28
ENG
With the rod fully wound and the chain
tensioner UP mark a facing upward,
install the gasket 1 and the chain ten-
sioner 2, and tighten the bolt 3 to the
specified torque.
T R..
Bolt (timing chain tensioner):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Release the screwdriver, check the ten-
sioner rod to come out and tighten the
gasket 4 and the cap bolt 5 to the speci-
fied torque.
T R..
Tensioner cap bolt:
7 Nm (0.7 m • kg, 5.1 ft • lb)
5
4New
3. Turn:
Crankshaft
Counterclockwise several turns
4. Check:
Rotor “I” mark
Align with the crankcase stationary
pointer.
Camshaft match marks
Align with the cylinder head surface.
Out of alignment → Adjust.
CAMSHAFTS

4 - 31
ENG

CYLINDER HEAD
ASSEMBLY AND INSTALLATION
1. Install:

Timing chain guide (front)
1

Dowel pin
2

Cylinder head gasket
3


Cylinder head
4
NOTE:

While pulling up the timing chain, install the
timing chain guide (front) and cylinder head.
New

2. Install:

Plain washer
1

Bolt [L=160 mm (6.30 in)]
2

Bolt [L=150 mm (5.91 in)]
3
Installation steps:
CAUTION:

Tighten the cylinder head using the rota-
tion angle procedure to obtain uniform
tightening torque.

Wash the threads and contact surfaces of
the bolts, the contact surfaces of the plain
washers, the contact surface of the cylin-
der head, and the threads of the crank-
case.

Apply the molybdenum disulfide grease on
the threads and contact surfaces of the
bolts and on both contact surfaces of the
plain washers.

Install the plain washers and bolts.

Tighten the bolts to the specified torque in
two or three steps in the proper tightening
sequence as shown.
T R..

Bolts (cylinder head):
1st:
30 Nm (3.0 m • kg, 22 ft • lb)

4 - 32
ENG


Remove the bolts.

Again apply the molybdenum disulfide
grease on the threads and contact sur-
faces of the bolts and on both contact sur-
faces of the plain washers.

Retighten the bolts.
NOTE:

Tighten the bolts to the specified torque in
two or three steps in the proper tightening
sequence as shown.
T R..

Bolts (cylinder head):
2nd:
20 Nm (2.0 m • kg, 14 ft • lb)

Put a mark on the corner
1
of the bolt
(cylinder head) and the cylinder head
2
as shown.
NOTE:

Tighten the bolts 90˚ in each of the two
steps to reach the specified angle of 180˚ in
the proper tightening sequence as shown.
T R..

Bolts (cylinder head):
Final:
Specified angle 180˚
1
2
180˚

3. Install:

Nut (cylinder head)
1
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4. Install:

Copper washer
1


Oil delivery pipe
2

Union bolt (M8)
3


Union bolt (M10)
4
New
T R..18 Nm (1.8 m · kg, 13 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)

CYLINDER HEAD

5 - 38
CHASFRONT FORK
26. Tighten:
Cap bolt (locknut) 1
NOTE:
While compressing the fork spring, set the
thin type spanners 2 between the spacer 3
and spring guide 4.
Hold the locknut 5 and tighten the cap bolt
with specified torque.
27. Install:
Cap bolt 1
To outer tube.
NOTE:
Temporarily tighten the cap bolt.
T R..29 Nm (2.9 m · kg, 21 ft · lb)
28. Install:
Protector guide 1
Installation
1. Install:
Front fork 1
NOTE:
Temporarily tighten the pinch bolts (under
bracket).
Do not tighten the pinch bolts (handle crown)
yet.
2. Tighten:
Cap bolt 1
3. Adjust:
Front fork top end a
Front fork top end (standard) a:
Zero mm (Zero in)
T R..30 Nm (3.0 m · kg, 22 ft · lb)