2003 YAMAHA TTR90 oil

4 - 44
ENGCRANKCASE AND CRANKSHAFT
Extent of removal:1 Timing chain removal2 Crankcase separation
3 Crankshaft removal
Extent of removal Order Part name Q’ty Remarks
Shift shaft Refer to “SHIFT SHAFT” section.
Oil pump and oil strainer Refer to “OIL PUMP” section.
Rotor and starter clutch Refer to “CDI MAGNETO AND
STARTER CLUTCH” section.
1 Timing chain guide (intake) 1
2 Timing chain 1
3 Crankcase (right) 1
4 Dowel pin 2
5 Crankshaft 1
6 Crankcase (left) 1
1
2
3

4 - 45
ENGCRANKCASE AND CRANKSHAFT
INSPECTION
Crankshaft
1. Measure:
Runout limit a
Connecting rod big end side clearance
b
Connecting rod big end radial clear-
ance c
Crank width d
Out of specification → Replace.
Use the dial gauge and a thickness
gauge.
Standard Limit
Runout
limit—0.03 mm
(0.0012 in)
Side
clearance0.10 ~ 0.40 mm
(0.0039 ~ 0.0157 in)—
Radial
clearance0.010 ~ 0.025 mm
(0.0004 ~ 0.0010 in)0.05 mm
(0.002 in)
Crack
width42.95 ~ 43.00 mm
(1.691 ~ 1.693 in)—
ASSEMBLY AND INSTALLATION
Crankcase
1. Apply:
Sealant
On the crankcase (left).
NOTE:
Clean the contacting surface of crankcase
(left and right) before applying the sealant.
DO NOT ALLOW any sealant to come in
contact with the oil gallery a.
Quick gasket®:
ACC-QUICK-GS-KT
YAMAHA Bond No. 1215:
90890-85505

5 - 1
CHAS

EC500000
CHASSIS
FRONT WHEEL AND REAR WHEEL
FRONT WHEEL AND FRONT BRAKE
FRONT WHEEL AND REAR WHEEL
Extent of removal:
1
Front wheel removal
2
Wheel bearing removal
3
Brake shoe plate assembly removal and disassembly
Extent of removal Order Part name Q’ty Remarks
FRONT WHEEL REMOVAL
WARNING

Support the machine securely so there is no
danger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
1 Bolt (brake cable holder) 1 Only loosening.
2 Brake cable 1 Disconnect at the lever side.
3 Wheel axle nut 1
4 Front wheel axle 1
5 Front wheel 1
6 Collar set 1
7 Brake shoe plate assembly 1
8 Oil seal 1
9Bearing
2Refer to “REMOVAL POINTS”.
2
31
3

5 - 5
CHAS

ROUE AVANT ET ROUE ARRIERE
VORDER- UND HINTERRAD
AUSBAU
Radlager (nach Bedarf)
1. Demontieren:

Lager
1

HINWEIS:

Die Lager mit einem Lageraustreiber
2
aus-
bauen.
PRÜFUNG
Rad
1. Messen:

Felgenschlag
Unvorschriftsmäßig
→
Instand setzen/
Erneuern.
Max. Felgenschlag
Höhenschlag
1
2,0 mm
Seitenschlag
2
2,0 mm
Bremsbeläge
1. Kontrollieren:


Trommelbremsbelag
Glasige Oberfläche
→
Anschleifen.
grobes Sandpapier verwenden.
HINWEIS:

Nach dem Anschleifen die Schleifpartikel mit
einem Lappen abwischen.
2. Messen:

Trommelbremsbelag-Stärke
Unvorschriftsmäßig
→
Erneuern.
HINWEIS:

Die Bremsbeläge und Federn als Satz erset-
zen, wenn eines der Teile bis zum Grenzwert
verschlissen ist.
Trommelbremsbelag-Stärke
a

Standard
vorne: 3,0 mm
hinten: 4,0 mm
Grenzwert
2,0 mm
POINTS DE DEPOSE
Roulement de roue (si nécessaire)
1. Déposer:

Roulement
1
N.B.:

Déposer le roulement en utilisant un arrache-roule-
ment courant
2
.
CONTROLE
Roue
1. Mesure:

Voile de roue
Hors limite → Réparer/changer.
Limite de voile de la roue:
Radial 1: 2,0 mm (0,08 in)
Latéral 2: 2,0 mm (0,08 in)
Garnitures de frein
1. Examiner:
Surface de garniture de mâchoire de frein
Zones brillantes → Poncer.
Utiliser du papier de verre à gros grains.
N.B.:
Après ce ponçage, éliminer les particules avec un
chiffon.
2. Mesurer:
Epaisseur de garniture de mâchoire de frein
Hors spécifications → Remplacer.
N.B.:
Remplacer les deux mâchoires de frein et ressorts si
l'une d'elles est usée à la limite.
Epaisseur de garniture de mâchoire
de frein a:
Standard:
avant: 3,0 mm (0,12 in)
arrière: 4,0 mm (0,16 in)
Limite:
2,0 mm (0,08 in)

5 - 7
CHAS

FRONT FORK
EC558000
FRONT FORK DISASSEMBLY
Extent of removal:
1
Oil seal removal
2
Damper rod removal
Extent of removal Order Part name Q’ty Remarks
FRONT FORK DISASSEMBLY
Preparation for disas-
semblyDrain the fork oil.
1
Adjuster 1
2
Fork spring 1
3
Dust cover 1
4
Stopper ring 1
5
Bolt (damper rod) 1 Use special tool.
Refer to “REMOVAL POINTS”.
6
Inner tube 1
7
Damper rod 1
8
Oil seal 1
9
Outer tube 1
1
2

5 - 8
CHASFRONT FORK
REMOVAL POINTS
Inner tube
1. Remove:
Bolt (damper rod)
NOTE:
While holding the damper rod with the damper
rod holder 1 and T-handle 2, loosen the bolt
(damper rod).
Damper rod holder:
YM-1300/90890-01294
T-handle:
YM-1326/90890-01326
EC555000
ASSEMBLY AND INSTALLATION
Front fork assembly
1. Install:
Oil seal 1
NOTE:
Press the oil seal into the outer tube with fork
seal driver weight 2 and fork seal driver
attachment 3.
2. Fill:
Fork oil
3. After filling up, slowly pump the fork up
and down to distribute the fork oil.
Fork seal driver weight:
YM-33963/90890-01184
Fork seal driver attachment:
90890-01186
Oil quantity:
64 cm3 (2.26 Imp oz, 2.16 US oz)
Recommended oil:
Fork oil 15W or equivalent

6 - 1
–+ELEC

12
3
456
7
0
98

A
B
F
EC
D

ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1
Main switch
2
“ENGINE STOP”
switch
3
Thermo switch
4
Ignition coil
5
CDI unit
6
Battery
7
Rectifier/regulator
8
Neutral switch
9
CDI magneto
0
Carburetor heater
A
Starter relay
B
Fuse
C
Start switch
D
Spark plug
E
Starter motor
F
Starting circuit cut-off
relay
COLOR CODE
B ...................... Black
Br .................... Brown
G ..................... Green
O ..................... Orange
R ..................... Red
Sb .................... Sky blue
W ..................... White
Y ...................... Yellow
EC612000
WIRING DIAGRAM
G/WB/RW/LW/RBr G
RW
B/WBr BRB/WBBrR
B/WB BB
BR/WBr B
GG/W
B/W
B/W
BrB/RWWOO
B
BW/LY/RR
W
B
B
R
W/RY/R
OFF RUNB
Y/R
Y
Y
OBO BY/RYB B
Sb
W W
Sb
ON OFF
OFFON
Y
BB
Y/R
Br
Br
B
B
R
RR
R
B
R/WR/W
R/WR/W
R/W
Sb
Sb
RB
R/WB R
Y/RRB W
B/WB
R/W
R/W
R/W
Sb
9
8
1 B5
4
D
2 3
=A
E 6
C
F 7

B/R ................... Black/Red
B/W .................. Black/White
G/W.................. Green/White
R/W .................. Red/White
W/L .................. White/Blue
W/R .................. White/Red
Y/R ................... Yellow/Red

–+ELEC

6 - 2
IGNITION SYSTEM
EC620000
IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
NOTE:


Remove the following parts before inspection.
1) Seat
2) Fuel tank

Use the following special tools in this inspection.
Spark gap testClean or replace
spark plug.
Check entire ignition
system for connection.Repair or replace.
Check main switch. Replace.
Check “ENGINE STOP”
switch.Replace.
Check ignition coil. Primary coil Replace.
Secondary coil Replace.
Check CDI magneto. Pickup coil Replace.
Source coil Replace.
Replace CDI unit.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754
Pocket tester:
YU-3112-C/90890-03112
No Spark
OK
OK
OK
OK
Spark
No good
No good
No good
No good
No good
No good
OK
No good