radiator YAMAHA YZ450F 2003 Betriebsanleitungen (in German)

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
CDI MAGNETO
........................................4-76
ENGINE REMOVAL
.................................4-80
CRANKCASE AND CRANKSHAFT
........4-85
TRANSMISSION, SHIFT CAM
AND SHIFT FORK
...................................4-94
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
.......5-1
FRONT BRAKE AND REAR BRAKE
.....5-10
FRONT FORK
..........................................5-26
HANDLEBAR
...........................................5-39
STEERING
...............................................5-45
SWINGARM
.............................................5-50
REAR SHOCK ABSORBER
....................5-58

GEN
INFO

1 - 1
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
Clutch lever
2
Hot starter lever
3
Front brake lever
4
Throttle grip
5
Radiator cap
6
Fuel tank cap
7
“ENGINE STOP” button
8
Kick starter
9
Fuel tank
0
Radiator
A
Coolant drain bolt
B
Rear brake pedal
C
Valve joint
D
Fuel cock
E
Cold starter knob
F
Drive chain
G
Air cleaner
H
Shift pedal
I
Oil dipstick
J
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.

GEN
INFO
1 - 7
SPECIAL TOOLS
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-1235, 90890-01235 Rotor holding tool
This tool is used when loosening or tightening the fly-
wheel magneto securing nut.YU-1235 90890-01235
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
YU-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
YU-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
YM-1189, 90890-01189 Flywheel puller
This tool is used to remove the flywheel magneto.YM-1189 90890-01189

1 - 14
GEN
INFO
DECOMPRESSION LEVER
INSTALLATION OF DECOMPRESSION
LEVER
Preparations
1. Remove the seat.
2. Drain the coolant.
Refer to “COOLANT REPLACEMENT”
section in the CHAPTER 3.
3. Remove:
Radiator
Refer to “RADIATOR” section in the
CHAPTER 4.
Cylinder head cover
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
Number plate
4. Remove:
Plug 1
Bolt 2
Plain washer 3
NOTE:
Make a hole in the resin side a and remove
the plug.
Installation
1. Install:
Oil seal 1
NOTE:
Install the oil seal, as shown, where the plug
was removed.
Apply the lithium soap base grease on the oil
seal lip.
2. Install:
Torsion spring 1
Decompression shaft 2
Plain washer 3
Bolt (decompression shaft) 4
Decompression cable guide 5
Bolt (decompression cable guide) 6
Decompression cable 7
NOTE:
When installing the decompression shaft,
install the torsion spring in the location as
shown.
For the decompression shaft securing bolt
and plain washer, use the ones removed
from the same machine.
Apply the engine oil on the decompression
shaft.
23
1 a
1B
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

SPEC

2 - 9
MAINTENANCE SPECIFICATIONS
Lubrication system:
Oil filter type Wire mesh 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 117.8 mm (4.6 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) 0.71 L (0.62 Imp qt, 0.75 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 37 3.7 27
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 20 2.0 14
Exhaust pipe protector M6
×
1.0 3 10 1.0 7.2
Clamp (cylinder head side) M5
×
0.8 1 3 0.3 2.2
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 cover M5
×
0.8 2 4 0.4 2.9
Hot starter plunger M12
×
1.0 1 2 0.2 1.4
Air filter element M6
×
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 3 0.3 2.2
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 10 1.0 7.2
Oil check bolt M6
×
1.0 1 10 1.0 7.2
Oil hose clamp–2 2 0.2 1.4
Clutch cover M6 × 1.0 7 10 1.0 7.2

SPEC
2 - 16
MAINTENANCE SPECIFICATIONS
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.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 42 4.2 30
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 frame (front) M10 × 1.25 1 65 6.5 47
Engine and frame (upper) M10 × 1.25 1 55 5.5 40
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine guard (lower) M8 × 1.25 1 23 2.3 17
Engine skid plate mounting M6 × 1.0 6 10 1.0 7.2
CDI unit bracket mounting M6 × 1.0 1 10 1.0 7.2
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 4 0.4 2.9
Air scoop and radiator panel (lower) M6 × 1.0 2 4 0.4 2.9
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 10 1.0 7.2
Number plate M6 × 1.0 1 7 0.7 5.1

2 - 21
SPEC

CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Fuel tank breather hose
2
Hot starter cable
3
Radiator hose 4
4
Cylinder head breather hose
5
Radiator hose 1
6
Oil tank breather hose
7
Hose guide
8
Brake hose
9
“ENGINE STOP” button lead
0
Clamp
A
Sub wire harness
B
TPS (throttle position sen-
sor) lead
C
Neutral switch lead
D
Oil hose
E
Radiator breather hose
F
CDI magneto lead
G
Carburetor breather hose
H
Overflow hose
Å
Pass the fuel tank breather hose
between the handlebar and ten-
sion bar, then insert its end into
the hole of the number plate.
ı
Pass the hot starter cable
between the cylinder head
breather hose, oil tank breather
hose and ignition coil, then on
the outside of the left engine
bracket.
Ç
Pass the cylinder head breather
hose on the outside of the radia-
tor hose 1 and on the inside of the
radiator pipe (radiator hose 4).
Î
Fit the brake hose into the
guides on the protector.
‰
Fasten the “ENGINE STOP”
button lead and sub wire har-
ness to the frame with a plastic
locking tie and cut off the tie
end.
ÏFasten the sub wire harness
and hot starter cable to the
frame at the white tape for the
sub wire harness with a plastic
locking tie and cut off the tie
end.
ÌFasten the sub wire harness to
the frame with a plastic locking
tie and cut off the tie end.
C
9
0
A
0
0
0
0
0
B
C
D
0 0 E 0 F 0
1
2 8
7
6
5
4
3GHG9A
D
E
C
B
A
A
C
BB
Ç ÎÅ
ıØ
˜ ˆ
Ò
Ô ÈÌ Ó Ì Ï ‰ ‰
∏
*
*

2 - 22
SPECCABLE ROUTING DIAGRAM
ÓPass the sub wire harness
between the engine brackets.
ÈMake sure that the TPS lead
coupler does not go outside the
chassis.
ÔFasten the TPS lead to the
frame with a plastic band.
Fasten the neutral switch lead
and oil hose together with a
plastic locking tie and cut off
the tie end.
ÒFasten the neutral switch lead
to the frame with a plastic
band.
˜Fasten the neutral switch lead,
CDI magneto lead and radiator
breather hose to the frame with
a plastic band.ˆPass the neutral switch lead,
CDI magneto lead and radiator
breather hose between the
radiator and frame.
ØFasten the neutral switch lead
and CDI magneto lead to the
cable guide with a plastic lock-
ing tie and cut off the tie end.
∏Pass the carburetor breather
hoses and overflow hose so
that all there hoses do not con-
tact the rear shock absorber.*Decompression cable (sup-
plied for Europe and optional
for other destinations)
Pass the decompression cable
under the middle radiator
mounting boss and on the out-
side of the neutral switch lead,
CDI magneto lead and radiator
breather hose.
C
9
0
A
0
0
0
0
0
B
C
D
0 0 E 0 F 0
1
2 8
7
6
5
4
3GHG9A
D
E
C
B
A
A
C
BB
Ç ÎÅ
ıØ
˜ ˆ
Ò
Ô ÈÌ Ó Ì Ï ‰ ‰
∏
*
*

2 - 23
SPECCABLE ROUTING DIAGRAM
1Cable holder
2CDI unit
3Hot starter cable
4Clutch cable
5Throttle cable (return)
6Throttle cable (pull)
7Ignition coil
8Radiator breather hose
9Radiator hose 4
0Cylinder head breather
hose
ACDI unit bracket
BCDI unit bandÅFasten the grommet of the clutch
cable with the cable holder.
ıPass the hot starter cable, clutch
cable and throttle cables through
the cable guides.
ÇPass the hot starter cable over the
top radiator mounting boss.
ÎPass the hot starter cable, clutch
cable and throttle cables between
the radiator and frame, then over
the middle radiator mounting
boss.
‰Pass the clutch cable and throttle
cables on the outside of the igni-
tion coil.
ÏPass the radiator breather hose at
the rear of the radiator, on the left
of the chassis, and then between
the frame and radiator hose 4.ÌInsert the CDI unit band over the
CDI unit bracket as far as possi-
ble.
ÓFirst install the CDI unit and CDI
unit band to the CDI unit bracket,
then the CDI unit bracket to the
frame.
0
8
92
BA
3
4
5
6
712 ÏÓÌ
ı
Ç
Î
‰ ÅB
A
A
B