2003 YAMAHA TTR90 brake

1 - 1
GEN
INFO

DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
“ENGINE STOP” switch
2
Main switch
3
Start switch
4
Front brake lever
5
Throttle grip
6
Fuel tank cap
7
Kick starter
8
Fuel tank
9
Air cleaner
0
Rear brake pedal
A
Fuel cock
B
Starter lever (choke)
C
Drive chain
D
Shift pedal
E
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.
14
5
6
23

1

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GEN
INFO
CONTROL FUNCTIONS
EC150000
CONTROL FUNCTIONS
MAIN SWITCH
Functions of the respective switch positions
are as follows:
ON: The engine can be started only at this
position.
OFF: All electrical circuits are switched off.
The key can be removed in this position.
“ENGINE STOP” SWITCH
The engine stop switch 1 is located on the left
handlebar. Continue pushing the engine stop
switch till the engine comes to a stop.
1
START SWITCH
The start switch 1 is located on the right han-
dlebar. Push this switch to crank the engine
with the starter.
1
SHIFT PEDAL
The gear ratios of the constant-mesh 3 speed
transmission are ideally spaced. The gears
can be shifted by using the shift pedal 1 on
the left side of the engine.
WARNING
When starting out on the machine, shift the
transmission into 1st after pulling in the
front brake lever and closing the throttle
grip.

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GEN
INFO
CONTROL FUNCTIONS
KICK STARTER
WARNING
Before starting the engine, be sure to shift
the transmission into neutral.
Rotate the kick starter 1 away from the
engine. Push the starter down lightly with your
foot until the gears engage, then kick smoothly
and forcefully to start the engine.
EC155001
THROTTLE GRIP
The throttle grip 1 is located on the right han-
dlebar; it accelerates or decelerates the
engine. For acceleration, turn the grip toward
you; for deceleration, turn it away from you.
1
EC156000
FRONT BRAKE LEVER
The front brake lever 1 is located on the right
handlebar. Pull it toward the handlebar to acti-
vate the front brake.
1
EC157000
REAR BRAKE PEDAL
The rear brake pedal 1 is located on the right
side of the machine. Press down on the brake
pedal to activate the rear brake.

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GEN
INFO
STARTING AND OPERATION
STARTING AND OPERATION
CAUTION:
Prior to operating the machine, perform
steps listed in pre-operation check list.
WARNING
Never start your engine or let it run for any
length of time in a closed area. The exhaust
fumes are poisonous and can cause loss of
consciousness and death within a short
time. Always operate your machine in an
area with adequate ventilation.
STARTING A COLD ENGINE
WARNING
Before starting the engine, be sure to shift
the transmission into neutral.
NOTE:
This model is equipped with an ignition cir-
cuit cut-off system. In case of electric start-
ing, the engine can be started only when the
transmission is in neutral.
If the engine fails to start by pushing the start
switch, release the switch, wait a few sec-
onds, and then try again. Each starting
attempt should be as short as possible to
preserve the battery. Do not crank the
engine more than 10 seconds on any one
attempt. If the engine does not start with the
starter motor, try using the kickstarter.
1. Turn the fuel cock to “ON”.
2. Turn the main switch to “ON”.
3. Shift the transmission into neutral.
4. Operate the starter (choke) and com-
pletely close the throttle grip.
5. Start the engine by pushing the start
switch or by kicking the kickstarter.
6. After the engine starts, warm up for one
or two minutes. Make sure the stater
(choke) is returned to the original position
before riding.STARTING A WARM ENGINE
To start a warm engine, refer to the “Starting a
cold engine” section. The starter (choke)
should not be used. The throttle should be
opened slightly.
CAUTION:
See “Engine break-in Section” prior to
operating engine for the first time.
WARMING UP
To get maximum engine life, always “warm-up”
the engine before starting off. Never acceler-
ate hard with a cold engine! To see whether or
not the engine is warm, see if it responds to
throttle normally with the stater (choke) turned
off.
WARNING
Before starting off, be sure to turn up or
remove the side stand.
Failure to retract the side stand completely
can result in a serious accident when you
try to turn a corner.
ENGINE BREAK-IN
Brake-in is important to better fit the moving
and sliding parts as well as the installed parts.
It is also important to accustom the rider to the
machine better.
Avoid full-throttle run on a new machine for the
first 5 hours.
After the trial run, check for loose parts, oil
leakage and other problems.
Make full inspection and adjustment especially
of slack cables and drive chain and loose
spokes.
CAUTION:
After the break-in period, check every fit-
ting and fastener for looseness.
If any loose is found, retighten it securely.

SPEC

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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
Generator system CDI magneto
Battery type GT4B-5
Battery voltage/capacity 12 V/2.5 AH
Specific gravity 1.350
GENERAL SPECIFICATIONS

SPEC
2 - 12
Drum brake:
Front drum brake type Leading, trailing ----
Rear drum brake type Leading, trailing ----
Front drum inside diameter 95 mm (3.74 in) 96 mm (3.78 in)
Rear drum inside diameter 110 mm (4.33 in) 111 mm (4.37 in)
Front lining thickness 3 mm (0.12 in) 2 mm (0.08 in)
Rear lining thickness 4 mm (0.16 in) 2 mm (0.08 in)
Front shoe spring free length 32.7 mm (1.29 in) ----
Rear shoe spring free length 50.5 mm (1.99 in) ----
Brake lever and brake pedal:
Brake lever free play (lever end) 10 ~ 20 mm (0.39 ~ 0.79 in) ----
Brake pedal free play 10 ~ 20 mm (0.39 ~ 0.79 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit
MAINTENANCE SPECIFICATIONS

SPEC
2 - 13
NOTE:
1. First, tighten the ring nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the ring nut
wrench and turn the steering right and left a few times; then loosen the ring nut one turn.
2. Retighten the ring nut 1 Nm (0.1 m • kg, 0.7 ft • lb).
-marked portion shall be checked for torque tightening after break-in or before each ride.Part to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
Engine mounting:
Engine and frame (front-upper) M8 × 1.25 1 30 3.0 22
Engine and frame (rear-upper) M8 × 1.25 1 26 2.6 19
Engine and frame (rear-lower) M10 × 1.25 1 48 4.8 35
Starter cable and frame M11 × 1.25 1 1 0.1 0.7
Pivot shaft and nut M10 × 1.25 1 30 3.0 22
Handle crown and steering shaft M10 × 1.25 1 40 4.0 29
Front fork cap bolt M20 × 1.0 2 40 4.0 29
Under bracket and front fork M10 × 1.25 2 33 3.3 24
Damper rod bolt M8 × 1.25 2 20 2.0 14
Handle crown and handlebar holder (lower) M10 × 1.25 2 40 4.0 29
Handlebar holder (upper) M8 × 1.25 4 23 2.3 17
Front brake cable holder and front fork M6 × 1.0 2 7 0.7 5.1
Steering ring nut M25 1 Refer to NOTE.
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and frame M6 × 1.0 2 7 0.7 5.1
Grab bar and frame M6 × 1.0 4 13 1.3 9.4
Front brake camshaft lever and camshaft M6 × 1.0 1 7 0.7 5.1
Rear brake camshaft lever and camshaft M6 × 1.0 1 7 0.7 5.1
Front wheel axle nut M10 × 1.25 1 35 3.5 25
Rear brake shoe plate tension bar M8 × 1.25 2 26 2.6 19
Wheel drive hub and driven sprocket M8 × 1.25 4 25 2.5 18
Rear wheel axle nut M12 × 1.25 1 60 6.0 43
Wheel nipple (spoke)—64 2 0.2 1.4
Drive chain guard M5 × 0.8 2 4 0.4 2.9
Drive chain support M5 × 0.8 3 4 0.4 2.9
Chain puller locknut M6 × 1.0 2 7 0.7 5.1
Footrest and frame M8 × 1.25 2 30 3.0 22
Battery box M6 × 1.0 3 5 0.5 3.6
MAINTENANCE SPECIFICATIONS

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SPEC

CABLE ROUTING DIAGRAM
CABLE ROUTING DIAGRAM
1
Crankcase breather hose
2
CDI magneto lead
3
Wire harness
4
Thermo switch
5
Thermo switch lead
6
CDI unit lead
7
Spark plug lead
8
Starter cable
9
Starter relay lead
0
Starter motor lead
A
Starter motor
B
Throttle cable
C
Brake cable
D
Engine stop switch lead
E
Main switch lead
F
Start switch lead
Å
Pass the spark plug lead
through the lead guide.
ı
Make sure that the starter cable
does not contact the engine
bracket.
Ç
Fasten the engine stop lead with
the plastic bands.
Î
Pass the brake cable through
the cable guide.
‰
Fasten the start switch lead with
the plastic bands.
30 ~ 40 mm
(1.18 ~ 1.57 in)A
B
40 ~ 50 mm
(1.57 ~ 1.97 in)
1
B
C
D
E ‰
F
ÎÎÇ A875 4
6 3
2
1
Å
ı
A
B
0
9