2004 YAMAHA WR 450F radiator

CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS
..................................4-1
EXHAUST PIPE AND SILENCER
.............4-3
RADIATOR
................................................4-5
CARBURETOR
..........................................4-8
CAMSHAFTS
...........................................4-21
CYLINDER HEAD
....................................4-29
VALVES AND VALVE SPRINGS
............4-33
CYLINDER AND PISTON
........................4-42
CLUTCH
...................................................4-48
OIL FILTER, WATER PUMP
AND CRANKCASE COVER (RIGHT)
.....4-55
BALANCER
.............................................4-62
OIL PUMP
................................................4-65
KICK AXLE AND SHIFT SHAFT
.............4-69
AC MAGNETO
AND STARTER CLUTCH
........................4-76
ENGINE REMOVAL
.................................4-83
CRANKCASE AND CRANKSHAFT
........4-89
TRANSMISSION, SHIFT CAM
AND SHIFT FORK
...................................4-98
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
.......5-1
FRONT BRAKE AND REAR BRAKE
.....5-11
FRONT FORK
..........................................5-27
HANDLEBAR
...........................................5-40
STEERING
...............................................5-46
SWINGARM
.............................................5-52
REAR SHOCK ABSORBER
....................5-60

GEN
INFO

1 - 1
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
Clutch lever
2
Hot starter lever
3
“ENGINE STOP” button
4
Trip meter
5
Main switch
6
Start switch
7
Front brake lever
8
Throttle grip
9
Radiator cap
0
Fuel tank cap
A
Taillight
B
Kickstarter
C
Fuel tank
D
Headlight
E
Radiator
F
Coolant drain bolt
G
Rear brake pedal
H
Valve joint
I
Fuel cock
J
Cold starter knob
K
Air cleaner
L
Drive chain
M
Shift pedal
N
Oil dipstick
O
Front fork
NOTE:


The machine you have purchased may differ
slightly from those shown in the following.

Designs and specifications are subject to
change without notice.
A
BCD
E
F G
1234
5
6
7
8
9 0
HI
J
K
L M
N O

GEN
INFO
1 - 7
EC140001
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the
correct special tool will help prevent damage caused by the use of improper tools or improvised
techniques. The shape and part number used for the special tool differ by country, so two types are
provided. Refer to the list provided to avoid errors when placing an order.
NOTE:
For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “ACC-”.
For others, use part number starting with “90890-”.
Part number Tool name/How to use Illustration
YU-1135-A, 90890-01135 Crankcase separating tool
These tool is used to remove the crankshaft from
either case.YU-1135-A 90890-01135
YU-3097, 90890-01252
YU-1256Dial gauge and stand
Stand
These tools are used to check each part for runout or
bend.YU-3097
YU-125690890-01252
YU-90050, 90890-01274
YU-90050, 90890-01275
YM-91044, 90890-04081
YU-90063, 90890-01278Crankshaft installing tool
Crankshaft installing pot
Crankshaft installing bolt
Spacer (crankshaft installer)
Adapter (M12)
These tools are used to install the crankshaft.YU-90050
YU-90063
YM-9104490890-01274
90890-01275
90890-01278
90890-04081
YU-1304, 90890-01304 Piston pin puller
This tool is used to remove the piston pin.YU-1304 90890-01304
YU-24460-01, 90890-01325
YU-33984, 90890-01352Radiator cap tester
Adapter
These tools are used for checking the cooling sys-
tem.YU-24460-01
YU-3398490890-01325
90890-01352
YU-33975, 90890-01403 Ring nut wrench
This tool is used when tighten the steering ring nut to
specification.YU-33975 90890-01403
YM-1423, 90890-01423 Damper rod holder
Use this tool to remove and install the damper rod.YM-1423 90890-01423
SPECIAL TOOLS

SPEC

2 - 9
MAINTENANCE SPECIFICATIONS
Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance “A”0.12 mm or less
(0.0047 in or less)0.20 mm
(0.008 in)
Tip clearance “B”0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)0.24 mm
(0.009 in)
Side clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)0.17 mm
(0.007 in)
Bypass valve setting pressure 40 ~ 80 kPa (0.4 ~ 0.8 kg/cm
2

,
5.69 ~ 11.38 psi)----
Cooling:
Radiator core size
Width 127.8 mm (5.0 in) ----
Height 260 mm (10.2 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2

, 15.6 psi) ----
Radiator capacity (total) 0.78 L (0.69 Imp qt, 0.82 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

SPEC

2 - 11
MAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Spark plug M10S
×
1.0 1 13 1.3 9.4
Camshaft cap M6
×
1.0 10 10 1.0 7.2
Cylinder head blind plug screw M12
×
1.0 1 28 2.8 20
Cylinder head (stud bolt) M6
×
1.0 2 7 0.7 5.1
M8
×
1.25 1 15 1.5 11
(bolt) M10
×
1.25 4 Refer to NOTE.*
1

(nut) M6
×
1.0 2 10 1.0 7.2
Cylinder head cover M6
×
1.0 2 10 1.0 7.2
Cylinder M6
×
1.0 1 10 1.0 7.2
Timing chain tensioner M6
×
1.0 2 10 1.0 7.2
Tensioner cap bolt M6
×
1.0 1 7 0.7 5.1
Timing chain guide (rear) M6
×
1.0 2 10 1.0 7.2
Exhaust pipe (nut) M8
×
1.25 1 13 1.3 9.4
(bolt) M8
×
1.25 1 24 2.4 17
Silencer M8
×
1.25 2 35 3.5 25
Silencer clamp M8
×
1.25 1 16 1.6 11
Exhaust pipe protector M6
×
1.0 3 10 1.0 7.2
Spark arrester (for USA) M6
×
1.0 3 10 1.0 7.2
Silencer end pipe (for USA) M6
×
1.0 1 10 1.0 7.2
Carburetor joint clamp (cylinder head side) M5
×
0.8 1 3 0.3 2.2
Carburetor joint clamp (carburetor side) M4
×
0.7 1 3 0.3 2.2
Air filter case M6
×
1.0 2 8 0.8 5.8
Air filter joint clamp M6
×
1.0 1 3 0.3 2.2
Air filter joint and air filter case M5
×
0.8 1 4 0.4 2.9
Throttle cable (pull) M6
×
1.0 1 4 0.4 2.9
Throttle cable (return) M12
×
1.0 1 11 1.1 8.0
Throttle cable cover M5
×
0.8 2 4 0.4 2.9
Hot starter plunger M12
×
1.0 1 2 0.2 1.4
Radiator panel (upper) M6
×
1.0 2 10 1.0 7.2
Radiator M6
×
1.0 6 10 1.0 7.2
Radiator hose clamp M6
×
1.0 8 2 0.2 1.4
Radiator pipe 1, 2 M10
×
1.0 2 10 1.0 7.2
Impeller M8
×
1.25 1 14 1.4 10
Water pump housing cover M6
×
1.0 3 10 1.0 7.2
Coolant drain bolt M6
×
1.0 1 10 1.0 7.2
Oil pump cover M4
×
0.7 1 2 0.2 1.4
Oil pump M6 × 1.0 3 10 1.0 7.2
Engine oil drain bolt (oil filter) M6 × 1.0 1 10 1.0 7.2
Oil filter cover M6 × 1.0 2 10 1.0 7.2
Oil delivery pipe 1 M10 × 1.25 1 20 2.0 14
M8 × 1.25 2 18 1.8 13
Oil delivery pipe 2 M6 × 1.0 1 10 1.0 7.2
Oil hose M6 × 1.0 2 8 0.8 5.8

SPEC
2 - 16
MAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear wheel axle and nut M20 × 1.5 1 125 12.5 90
Driven sprocket and wheel hub M8 × 1.25 6 50 5.0 36
Nipple (spoke)–72 3 0.3 2.2
Disc cover and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Chain puller adjust bolt and locknut M8 × 1.25 2 16 1.6 11
Engine mounting:
Engine upper bracket and frame M10 × 1.25 2 55 5.5 40
Engine lower bracket and frame M8 × 1.25 4 34 3.4 24
Engine and engine bracket (front) M10 × 1.25 1 69 6.9 50
Engine and engine bracket (upper) M10 × 1.25 1 52 5.2 37
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine guard (left and right) M8 × 1.25 2 23 2.3 17
Engine skid plate mounting M6 × 1.0 6 10 1.0 7.2
Regulator bracket mounting M6 × 1.0 2 7 0.7 5.1
Regulator mounting M6 × 1.0 2 7 0.7 5.1
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 80 8.0 58
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame and frame (upper) M8 × 1.25 1 32 3.2 23
Rear frame and frame (lower) M8 × 1.25 2 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 1 0.1 0.7
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Drive chain tensioner mounting (upper) M8 × 1.25 1 19 1.9 13
Drive chain tensioner mounting (lower) M8 × 1.25 1 20 2.0 14
Chain support and swingarm M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank mounting M6 × 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M6 × 1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M6 × 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Seat mounting M8 × 1.25 2 23 2.3 17
Side cover mounting M6 × 1.0 2 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 6 6 0.6 4.3
Air scoop and radiator panel (lower) M6 × 1.0 2 6 0.6 4.3
Front fender mounting M6 × 1.0 4 7 0.7 5.1
Rear fender mounting (front) M6 × 1.0 2 7 0.7 5.1
Rear fender mounting (rear) M6 × 1.0 2 11 1.1 8.0
Trip meter mounting M6 × 1.0 2 7 0.7 5.1

2 - 23
SPEC

CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Fuel tank breather hose
2
Clamp
3
Diode
4
Wire harness
5
Hot starter cable
6
Negative battery lead
7
Starter motor lead
8
TPS (throttle position sen-
sor) lead
9
Neutral switch lead
0
Oil hose
A
Hose holder
B
Radiator hose 4
C
Cylinder head breather hose
D
AC magneto lead
E
Radiator hose 1
F
Oil tank breather hose
G
Brake hose
H
Hose guide
I
Carburetor breather hose
J
Overflow hose
K
Coolant reservoir tank breather
hose
Å
Insert the fuel tank breather
hose into the hole in the steering
shaft cap.
ı
Fasten the diode of the wire har-
ness and rectifier/regulator lead
(at its protecting tube) to the
frame at the white tape for the
diode with a plastic locking tie
and cut off the tie end.
Ç
Fasten the wire harness, recti-
fier/regulator lead, coolant res-
ervoir hose and hot starter cable
to the frame with a plastic lock-
ing tie and cut off the tie end.
Î
Fasten the wire harness, recti-
fier/regulator lead and coolant
reservoir hose to the frame with
a plastic locking tie and cut off
the tie end.
‰
Fasten the wire harness to the
frame at its white tape with a
plastic locking tie and cut off the
tie end.

2 - 24
SPEC

CABLE ROUTING DIAGRAM
Ï
Fasten the wire harness, TPS
lead (in the wire harness),
starter motor lead and negative
battery lead to the frame with a
plastic locking tie and cut off
the tie end.
Ì
Make sure that the TPS cou-
pler does not go out the chas-
sis.
Ó
Fasten the TPS lead to the
frame with a plastic band.
È
Fasten the neutral switch lead
and oil hose together with the
plastic locking ties and cut off
the tie ends.
ÔPass the cylinder head
breather hose through the
hose holders.Fasten the neutral switch lead
to the frame with a plastic band
ends outward.
ÒFasten the neutral switch lead
and AC magneto lead to the
frame with a plastic band ends
outward.
˜Pass the cylinder head
breather hose on the outside of
the radiator hose 1 and on the
inside of the radiator pipe (radi-
ator hose 4).
ˆPass the oil tank breather hose
on the outside of the AC mag-
neto lead, neutral switch lead,
wire harness and cylinder head
breather hose.ØPass the wire harness on the
outside of the neutral switch
lead and AC magneto lead.
∏Fit the brake hose into the
guides on the protector.
ŒPass the wire harness through
the cable guide.
ÂFasten the AC magneto lead
and neutral switch lead to the
cable guide at their protecting
tube with a plastic locking tie
and cut off the tie end.
ÍPass the carburetor breather
hoses, overflow hose and cool-
ant reservoir tank breather
hose so that the hoses do not
contact the rear shock
absorber.