2001 YAMAHA TTR90 ignition

CHAPTER 4
ENGINE
CARBURETOR
......................................... 4-1
CYLINDER HEAD
..................................... 4-8
CAMSHAFT AND ROCKER ARMS
....... 4-13
VALVES AND VALVE SPRINGS
........... 4-16
CYLINDER AND PISTON
....................... 4-21
CLUTCH
.................................................. 4-27
KICK AXLE
............................................. 4-33
SHIFT SHAFT
......................................... 4-34
OIL PUMP
............................................... 4-36
CDI MAGNETO
....................................... 4-39
CRANKCASE AND CRANKSHAFT
....... 4-41
SHIFT FORK, SHIFT CAM AND
TRANSMISSION
..................................... 4-44
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
...... 5-1
FRONT FORK
........................................... 5-6
HANDLEBAR
............................................ 5-9
STEERING
.............................................. 5-10
SWINGARM
............................................ 5-11
CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS AND
WIRING DIAGRAM
................................... 6-1
IGNITION SYSTEM
................................... 6-2
CARBURETOR HEATING SYSTEM
........ 6-6
MAINTENANCE RECORD
....................... 6-9

GEN
INFO

1 - 7
SPECIAL TOOLS
YM-1312-A, 90890-01312Fuel level gauge
This gauge is used to measure the fuel level in the
float chamber.YM-1312-A 90890-01312
YM-01326, 90890-01326 T-handle
This tool is used for holding the damper rod holder
when removing or installing the damper rod holder.YM-01326 90890-01326
90890-01186 Fork seal driver attachment
This tool is used to installing the oil seal.90890-01186
YM-8035, 90890-01311 Valve adjusting tool
This tool is necessary for adjusting valve clearance.YM-8035 90890-01311
YM-33963, 90890-01184 Fork seal driver weight
This tool is used to installing the oil seal.YM-33963 90890-01184
YM-34487
90890-06754Dynamic spark tester
Ignition checker
This instrument is necessary for checking the ignition
system components.YM-34487 90890-06754
YM-33975, 90890-01403 Ring nut wrench
This tool is used when tighten the steering ring nut to
specification.YM-33975 90890-01403
YM-91042, 90890-04086 Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.YM-91042 90890-04086
YS-1880-A, 90890-01701 Sheave holder
This tool is used for when loosening or tightening the
flywheel magneto securing nut.YS-1880-A 90890-01701
Part number Tool name/How to use Illustration

SPEC

2 - 3
Brake:
Front brake type Drum brake
Operation Right hand operation
Rear brake type Drum brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 110 mm (4.33 in)
Rear wheel travel 93 mm (3.66 in)
Electrical:
Ignition system CDI magneto
GENERAL SPECIFICATIONS

SPEC

2 - 14
EC212300
ELECTRICAL
Item Standard Limit
CDI:
Magneto-model/manufacturer F5HN 00/YAMAHA ----
Source coil resistance (color) 688 ~ 1,032
W
at 20 ˚C (68 ˚F)
(Brown – Green)----
Pickup coil resistance (color) 248 ~ 372
W
at 20 ˚C (68 ˚F)
(Red – White)----
CDI unit-model/manufacturer 4GL-20/YAMAHA ----
Ignition coil:
Model/manufacturer 4KJ-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary winding resistance 0.18 ~ 0.28
W
at 20 ˚C (68 ˚F) ----
Secondary winding resistance 6.3 ~ 9.5 k
W
at 20 ˚C (68 ˚F) ----
Spark plug cap:
Type Resin ----
Resistance 10 k
W
at 20 ˚C (68 ˚F) ----
MAINTENANCE SPECIFICATIONS

2 - 16
SPEC

CABLE ROUTING DIAGRAM
CABLE ROUTING DIAGRAM
1
Crankcase breather hose
2
Wire harness
3
CDI magneto lead
4
Starter cable
5
Carburetor heating lead
6
Engine stop switch lead
7
Thermo switch
8
Thermo switch lead
9
Spark plug lead
0
Throttle cable
A
Cable holder
B
Fuel tank breather hose
C
Brake cable

After fastening the starter cable, CDI magneto lead, wire harness and
thermo switch lead, cut off any excess from the plastic locking tie end.
õ
Pass the ignition coil lead through the lead guide.
‚
Fasten the engine stop switch lead with the plastic bands.
ë
Pass the brake cable through the cable guides.
12345
9
0
B A
6
C 1
õ
‚
ë
ë
A
A
67
8
20 ~ 30 mm
(0.79 ~ 1.18 in)

2 - 17
SPEC

CABLE ROUTING DIAGRAM
1
Cable guide
2
Brake cable
3
Throttle cable
4
Fuel tank breather hose
5
Engine stop switch lead
6
Air vent hose
7
Air intake duct
8
Ignition coil
9
Cable guide
0
Wire harness
A
Damper
B
CDI unit lead
C
CDI unit
D
Rectifier/regulator lead
E
Rectifier/regulator
F
Crankcase breather hose
G
Carburetor breather hose
H
Spark plug lead
I
Fuel hose
J
Starter cable
K
CDI magneto lead
L
Thermo switch
A
123
4
5
6
7
8
9
0A
C
E B
F G H I
6
6 J L
5
H
B8 K
7 ‚
ä
‚
ì
í
B - B C - C
D - DF - FE
õ
ë
D
D
B
D
A A B
B B
B
C
C C
CE
B D
B
D
F F F F

4 - 6
ENGCARBURETOR
EC464600
Float
1.Inspect:
lFloat 1
Damage ® Replace.
ASSEMBLY AND INSTALLATION
Carburetor
1.Install:
lPilot air screw 1
Note the following installation points:
lScrew in the pilot air screw until it is lightly
seated.
lBack out it by the specified number of
turns.
Pilot air screw:
1-3/4 turns out
2.Install:
lThrottle valve 1
lStarter plunger 2
NOTE:
Align the slit a of the throttle valve with the tab
b of the carburetor top.
FUEL LEVEL ADJUSTMENT
WARNING
Gasoline (fuel) and its vapors are highly
flammable and explosive. Keep away from
sparks, cigarettes, flames or other sources
of ignition.

6 - 1
–+ELEC

ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1
CDI magneto
2
CDI unit
3
Ignition coil
4
Spark plug
5
“ENGINE STOP” switch
6
Thermo switch
7
Carburetor heater
8
Rectifier/regulator
COLOR 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