2005 YAMAHA TTR90 engine

5 - 3
CHAS

FRONT WHEEL AND REAR WHEEL
REAR WHEEL AND REAR BRAKE
Extent of removal:
1
Rear wheel removal
2
Wheel bearing removal
3
Brake shoe plate assembly removal and disassembly
Extent of removal Order Part name Q’ty Remarks
REAR 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 Brake rod 1
2 Cotter pin 1
3 Nut (tension bar) 1
4 Bolt (tension bar) 1
5 Wheel axle nut 1
6 Rear wheel axle 1
7 Drive chain puller 2
8 Rear wheel 1
9 Collar (right) 1
10 Brake shoe plate assembly 1
231

5 - 6
CHAS

FRONT FORK
EC550000
FRONT FORK
Extent of removal:
1
Front fork removal
Extent of removal Order Part name Q’ty Remarks
FRONT FORK 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.
Front wheel Refer to “FRONT WHEEL AND REAR
WHEEL” section.
Handlebar Refer to “HANDLEBAR” section.
Front fender
1 Brake cable holder 1
2 Cap bolt 1
3 Adjuster 1 Only loosening.
4 Pinch bolt (under bracket) 1 Only loosening.
5 Front fork 1
1

5 - 9
CHASHANDLEBAR
EC5B0000
HANDLEBAR
TT-R90
Extent of removal:1 Handlebar removal
Extent of removal Order Part name Q’ty Remarks
HANDLEBAR REMOVAL
1“ENGINE STOP” switch 1
2 Brake lever cable 1 Disconnect at the lever side.
3 Brake lever 1
4 Grip cap (lower) 1
5 Grip cap (upper) 1
6 Throttle cable 1 Disconnect at the throttle side.
7 Grip (right) 1
8 Tube guide 1
9 Grip (left) 1
10 Handlebar holder (upper) 2
11 Handlebar 1
12 Handlebar holder (lower) 2
1

5 - 10
CHASHANDLEBAR
TT-R90E
Extent of removal:1 Handlebar removal
Extent of removal Order Part name Q’ty Remarks
HANDLEBAR REMOVAL
1 Main switch 1
2 Start switch 1
3“ENGINE STOP” switch 1
4 Brake lever cable 1 Disconnect at the lever side.
5 Brake lever 1
6 Grip cap (lower) 1
7 Grip cap (upper) 1
8 Throttle cable 1 Disconnect at the throttle side.
9 Grip (right) 1
10 Tube guide 1
11 Grip (left) 1
12 Handlebar holder (upper) 2
13 Handlebar 1
14 Handlebar holder (lower) 2
1

5 - 11
CHASSTEERING
EC560000
STEERING
LS
LS
T R..TIGHTENING STEPS:
•Tighten ring nut.
38 Nm (3.8 m • kg, 27 ft • Ib)
•Loosen it completely.
•Retighten it.
1 Nm (0.1 m • kg, 0.7 ft • Ib)
T R..40 Nm (4.0 m • kg, 29 ft • Ib)
5 9681076 43
21
Extent of removal:1 Under bracket removal2 Bearing removal
Extent of removal Order Part name Q’ty Remarks
STEERING REMOVAL
WARNINGSupport the machine securely so there is nodanger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Front fork Refer to “FRONT FORK” section.
1 Steering stem bolt 1
2 Handle crown 1
3 Ring nut 1 Use special tool.
Refer to “STEERING HEAD INSPEC-
TION AND ADJUSTMENT” section in
the CHAPTER 3.
4 Ball race cover 1
5 Under bracket 1
6 Bearing inner race 2
7 Upper bearing ball 19
8 Lower bearing ball 16
9 Dust seal 1
10 Bearing outer race 2
2
1

5 - 12
CHASSWINGARM
EC570000
SWINGARM
Extent of removal:1 Swingarm removal2 Rear shock absorber removal
Extent of removal Order Part name Q’ty Remarks
SWINGARM REMOVAL
WARNINGSupport the machine securely so there is nodanger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Rear wheel Refer to “FRONT WHEEL AND REAR
WHEEL” section.
Rear fender
Drive chain
1 Cotter pin 2
2 Pin 2
3 Rear shock absorber 1
4 Pivot shaft 1 Hold the swingarm.
5 Swing arm 1
6 Drive chain guide 1
7 Drive chain guard 1
8 Drive chain support 1
1
2

6 - 1
–+ELECELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
TT-R90
EC611000
ELECTRICAL COMPONENTS
1CDI magneto
2CDI unit
3Ignition coil
4Spark plug
5“ENGINE STOP” switch
6Thermo switch
7Carburetor heater
8Rectifier/regulatorCOLOR CODE
B...................... Black
Br .................... Brown
G ..................... Green
O ..................... Orange
R ..................... Red
W..................... White
EC612000
WIRING DIAGRAM
G/WB/RW/LW/RBr G
RW
WB
Y/R
O
BO
B
B
BY/RY
WY/RB
W
Y
B
GG/W
B/W
B/W
BrB/RWWWY
OO
BBW/LY/RR
W
B
B
B
W/R
Y/R
OFF
RUN
B
Y/R
B
B
Y
Y
1
23
4
5 6
7 8
B/R ................... Black/Red
B/W .................. Black/White
G/W.................. Green/White
W/L .................. White/Blue
W/R .................. White/Red

6 - 2
–+ELEC
12
3
456
7
0
98
A
B
F
EC
D
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
TT-R90E
EC611000
ELECTRICAL COMPONENTS
1Main switch
2“ENGINE STOP”
switch
3Thermo switch
4Ignition coil
5CDI unit
6Battery
7Rectifier/regulator
8Neutral switch9CDI magneto
0Carburetor heater
AStarter relay
BFuse
CStart switch
DSpark plug
EStarter motor
FStarting circuit cut-off
relayCOLOR 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/WBB
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
BBY/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