2000 YAMAHA TTR90 fuel

IMPORTANT NOTICE
This machine is designed for off-road use only
by young operators under adult instruction and
supervision. It is illegal for this machine to be
operated on any public street, road, or high-
way.
Off-road use on public lands may be illegal.
Please check local regulations before riding.
1. GASOLINE IS HIGHLY FLAMMABLE:
* Always turn off the engine when refu-
eling.
* Take care not to spill on the engine or
exhaust pipe/muffler, when refueling.
* Never refuel while smoking or in the
vicinity of an open flame.
2. If you should swallow some gasoline or
inhale a lot of gasoline vapor, or allow
some gasoline to get in your eye(s), see
your doctor immediately. If any gasoline
spills on your skin or clothing, immedi-
ately wash it with soap and water, and
change your clothes.
3. Always turn off the engine before leaving
the machine unattended. When parking
the machine, note the following:
* The engine and exhaust pipe(s)/muf-
fler(s) may be hot. Park the machine
in a place where pedestrians or chil-
dren are not likely to touch the
machine.
* Do not park the machine on a slope or
soft ground; the machine may over-
turn.
SAFETY INFORMATION

4. When transporting the machine in
another vehicle, be sure is kept upright
and that the fuel cock is turned to the
“OFF”. If it should lean over, gasoline
may leak out of the carburetor or fuel
tank.
5. Never start your engine or let it run for
any length of time in a closed area. The
exhaust fumes are poisonous and may
cause loss of consciousness and death
within a short time. Always operate your
machine in an area with adequate venti-
lation.
6. Always wear a helmet, gloves, boots,
trousers, and jacket for motocross riding.

CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION
.......................................... 1-1
MACHINE IDENTIFICATION
.................... 1-2
IMPORTANT INFORMATION
................... 1-3
CHECKING OF CONNECTION
................ 1-5
SPECIAL TOOLS
...................................... 1-6
CONTROL FUNCTIONS
........................... 1-9
FUEL
....................................................... 1-11
STARTING AND OPERATION
............... 1-12
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS
................... 2-1
MAINTENANCE SPECIFICATIONS
......... 2-4
GENERAL TORQUE
SPECIFICATIONS
.................................. 2-15
DEFINITION OF UNITS
.......................... 2-15
CABLE ROUTING DIAGRAM
................ 2-16
CHAPTER 3
REGULAR INSPECTION AND
ADJUSTMENTS
MAINTENANCE INTERVALS
................... 3-1
PERIODIC MAINTENANCE AND
LUBRICATION
.......................................... 3-1
PRE-OPERATION INSPECTION AND
MAINTENANCE
........................................ 3-2
ENGINE
..................................................... 3-3
CHASSIS
................................................. 3-11
ELECTRICAL
.......................................... 3-19

1 - 1
GEN
INFO

DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
“ENGINE STOP” button
2
Front brake lever
3
Throttle grip
4
Fuel tank cap
5
Kick starter
6
Fuel tank
7
Air cleaner
8
Rear brake pedal
9
Fuel cock
0
Starter lever (choke)
A
Drive chain
B
Shift pedal
C
Front fork
NOTE:

l
The machine you have purchased may differ
slightly from those shown in the following.
l
Designs and specifications are subject to
change without notice.
1
1

GEN
INFO

1 - 6
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:

l
For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “YS-”.
lFor others, use part number starting with “90890-”.
Part number Tool name/How to use Illustration
YU-1083-A
90890-01084
90890-01085Small slide hammer set
Weight
Slide hammer
These tools are used when removing or installing the
rocker arm shafts.YU-1083-A 90890-01084
90890-01085
YU-01268, 90890-01268 Ring nut wrench
This tool is used when loosen the steering ring nut to
specification.YU-01268 90890-01268
YU-03112, 90890-03112 Yamaha pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.YU-03112 90890-03112
YU-8036-1
90890-03113Inductive tachometer
Engine tachometer
This tool is needed for observing engine rpm.YU-8036-1 90890-03113
YM-01253, 90890-01253 Valve spring compressor
This tool is needed to remove and install the valve
assemblies.YM-01253 90890-01253
YM-01300
90890-01294Damper rod holder set
Damper rod holder
Use this tool to remove and install the damper rod.YM-01300 90890-01294
YM-01312-A, 90890-01312Fuel level gauge
This gauge is used to measure the fuel level in the
float chamber.YM-01312-A 90890-01312

1 - 10
GEN
INFO
CONTROL FUNCTIONS
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.
EC158001
FUEL COCK
The fuel cock supplies fuel from the tank to
carburetor while filtering the fuel. The fuel cock
has the three positions:
OFF: With the lever in this position, fuel will
not flow. Always return the lever to this
position when the engine is not running.
ON: With the lever in this position, fuel flows
to the carburetor. Normal riding is done
with the lever in this position.
RES: This indicates reserve. If you run out of
fuel while riding, move the lever to this
position. FILL THE TANK AT THE
FIRST OPPORTUNITY. BE SURE TO
SET THE LEVER TO “ON” AFTER
REFUELING.
EC159000
STARTER LEVER (CHOKE)
When cold, the engine requires a richer air/fuel
mixture for starting. A separate starter circuit,
which is controlled by the starter lever 1, sup-
plies this mixture.
Pull the lever out to open the circuit (for start-
ing) and push the lever in to close the circuit.

1 - 11
GEN
INFO
CONTROL FUNCTIONS/FUEL
FUEL TANK CAP
Remove the fuel tank cap 1 by turning
counter-clockwise.
WARNING
Do not overfill the fuel tank. Avoid spilling
fuel on the hot engine.
FUEL
Use regular gasoline. Always use fresh, name
brand gasoline.
WARNING
Do not overfill the fuel tank. Avoid spilling
fuel on the hot engine. Do not fill the fuel
tank above the bottom of the filler tube 1
as shown in the illustration or it may over-
flow when the fuel heats up later and
expands.
aFuel level
Recommended fuel:
UNLEADED FUEL RECOM-
MENDED
Fuel tank capacity:
Total:
4.1 L (0.90 lmp gal, 1.08 US gal)
Reserve:
0.5 L (0.11 lmp gal, 0.13 US gal)

GEN
INFO
1 - 12
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.
1. Turn the fuel cock to “ON”.
2. Operate the starter (choke) and com-
pletely close the throttle grip.
3. Slide the “ENGINE STOP” switch to the
“”.
4. Kick the kick starter with full strength to
start the engine.
5. 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 “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
1. Prior to starting, fill fuel tank with gasoline
and oil tank with specified oil.
2. Allow engine to warm up. Check engine
idling speed. Check operating controls
and engine stop switch operation.
3. Operate machine in lower gears at mod-
erate throttle setting for 3 ~ 5 minutes.
Check spark plug condition.
4. Allow engine to cool. Repeat procedure,
running for 5 minutes. Very briefly, shift to
higher gears and check full throttle
response. Check spark plug condition.
5. Allow engine to cool. Repeat procedure,
running for 5 minutes. Full throttle and
higher gears may be used, but avoid sus-
tained full throttle operation. Check spark
plug condition.
6. Allow engine to cool. Remove top end and
inspect. Remove “high” spots on piston
with No.600 grit, wet sandpaper.
Clean, and carefully reassemble.
7. Check entire unit for loose or misadjusted
fittings/controls/fasteners.
8. Re-start engine and check through entire
operating range thoroughly. Stop. Check
spark plug condition. Re-start. After 10 ~
15 minutes operation, machine is ready
to ride.
CAUTION:
After the break-in period, check every fit-
ting and fastener for looseness.
If any loose is found, retighten it securely.