2000 YAMAHA TTR90 transmission

6. When going for riding, be sure to be with
your family.
Never go alone.
7. Before riding the machine, ask your par-
ents to check the machine very carefully.
8. Don’t touch the areas shown, or you’ll get
burnt in the hand.
9. Don’t touch rotating or moving parts.
10. Before starting the engine, be sure to shift
the transmission into neutral.

ABGEBILDETEN SYMBOLS
Die unter 1 bis 6 abgebildeten Symbole wei-
sen auf die Themen der einzelnen Kapitel hin.
1Allgemeine Angaben
2Technische Daten
3Regelmäßige Inspektionen und Einstellarbeiten
4Motor
5Fahrwerk
6Elektrische Anlage
Die Symbole 7 bis D weisen auf wichtige An-
gaben im Text hin.
7Wartung mit montiertem Motor möglich
8Spezialwerkzeug
9Art und Menge einzufüllender Flüssigkeiten
0Schmiermittel
AAnzugsmoment
BVerschleißgrenzen, Toleranzen
CMotordrehzahl
DElektrische Sollwerte
Die Symbole E bis I werden in den Explosi-
onszeichnungen verwendet und weisen auf
Schmier- und Klebemittel sowie die entspre-
chenden Stellen hin.
EGetriebeöl
FMotoröl
GMolybdändisulfidöl
HLeichtes Lithiumfett
IMolybdändisulfidfett
Die Symbole J bis K in den Explosionszeich-
nungen weisen darauf hin, wann Kleber J
aufgetragen wird und neue Bauteile K ver-
wendet werden.
JKlebemittel (LOCTITE®)
KErneuern
SYMBOLES GRAPHIQUES
(Voir l’illustration)
Les symboles graphiques 1 à 6 servent à repérer
les différents chapitres et à indiquer leur contenu.
1Renseignements généraux
2Caractéristiques
3Contrôles et réglages courants
4Moteur
5Partie cycle
6Partie électrique
Les symboles graphiques 7 à D permettent
d’identifier les spécifications encadrées dans le
texte.
7Avec de montage du moteur
8Outil spécial
9Liquide de remplissage
0Lubrifiant
ASerrage
BValeur spécifiée, limite de service
CRégime du moteur
DRésistance (W), tension (V), intensité (A)
Les symboles graphiques E à I utilisés dans les
vues en éclaté indiquent les endroit à lubrifier et le
type de lubrifiant.
EAppliquer de l’huile de transmission
FAppliquer de l’huile moteur.
GAppliquer de l’huile au bisulfure de molybdène
HAppliquer de la graisse fluide à base de savon au
lithium
IAppliquer de la graisse au bisulfure de molybdène
Les symboles graphiques J à K dans les vues en
éclaté indiquent l’agent de blocage J à appliquer
et les pièces K qui nécessitent un remplacement.
JAppliquer un agent de blocage (LOCTITE®)
KChanger

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

DESCRIPTION
FAHRZEUGBESCHREIBUNG
ALLGEMEINE ANGABEN
FAHRZEUGBESCHREIBUNG
1
Motorstoppschalter
2
Handbremshebel
3
Gasdrehgriff
4
Motoröl-Einfüllschraubverschluß/Tauchstab
5
Kickstarter
6
Kraftstofftank
7
Luftfilter
8
Fußbremshebel
9
Kraftstoffhahn
0
Chokehebel
A
Antriebskette
B
Schalthebel
C
Teleskopgabel
HINWEIS:

l
Leichte Modell-Abweichungen möglich.
l
Änderungen an Design und technischen Da-
ten jederzeit vorbehalten.
RENSEIGNEMENTS
GENERAUX
DESCRIPTION
1
Coupe-circuit du moteur
2
Levier de frein avant
3
Poignée d’accélérateur
4
Bouchon d’orifice de remplissage et jauge d’huile
5
Kick
6
Réservoir de carburant
7
Filtre à air
8
Pédale de frein arrière
9
Robinet à essence
0
Levier de starter
A
Chaîne de transmission
B
Pédale de sélection
C
Fourche avant
N.B.:

l
Votre machine diffère peut-être partiellement de
celles montrées sur ces photos.
l
La conception et les caractéristiques peuvent
êtres changées sans préavis.
1 - 1
1

1 - 9
GEN
INFO
CONTROL FUNCTIONS
EC150000
CONTROL FUNCTIONS
EC151000
“ENGINE STOP” SWITCH
Make sure that the engine stop switch 1 is
positioned to “ ”. The engine stop switch has
been equipped to ensure safety in an emer-
gency such when the machine is up set or
trouble takes place in the throttle system. The
engine will not start or run when the engine
stop switch is turned to “ ”.
EC153000
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.
EC154000
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.
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.

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.

SPEC

2 - 2
Fuel:
Type Unleaded fuel (USA)
Premium unleaded gasoline (CDN, Europe)
Unleaded fuel only (AUS)
Premium gasoline (Oceania)
Tank capacity 4.1 L (0.90 lmp gal, 1.08 US gal)
Reserve amount 0.5 L (0.11 Imp gal, 0.13 US gal)
Carburetor:
Type VM16SH
Manufacturer MIKUNI
Spark plug:
Type CR6HSA/U20FSR-U
Manufacturer NGK/DENSO
Gap 0.6 ~ 0.7 mm (0.02 ~ 0.03 in)
Clutch type: Wet, multiple-disc and centrifugal automatic
Transmission:
Primary reduction system Spur gear
Primary reduction ratio 67/18 (3.722)
Secondary reduction system Chain drive
Secondary reduction ratio 35/14 (2.500)
Transmission type Constant mesh, 3-speed
Operation Left foot operation
Gear ratio: 1st 37/13 (2.846)
2nd 33/19 (1.736)
3rd 28/23 (1.217)
Chassis:
Frame type Double cradle
Caster angle 24.83˚
Trail 56.0 mm (2.2 in)
Tire:
Type With tube
Size (front) 2.50-14 4PR
Size (rear) 3.00-12 4PR
Manufacturer (front and rear) CHENG SHIN
Type (front and rear) KNOBBY
Tire pressure (front and rear) 100 kPa (1.00 kg/cm
2

, 14.5 psi)
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)
GENERAL SPECIFICATIONS
2

2 - 4
SPEC

CARACTERISTIQUES D’ENTRETIEN
CARACTERISTIQUES D’ENTRETIEN
MOTEUR
Désignation Standard Limite
Culasse:
Limite de déformation ---- 0,03 mm
(0,0012 in)
Cylindre:
Alésage 47,000 à 47,005 mm
(1,8504 à 1,8506 in)47,05 mm
(1,8524 in)
Limite d’ovalisation ---- 0,03 mm
(0,001 in)
Arbre à cames:
Méthode d’entraînement Transmission par chaîne
(côté gauche)----
Dimensions de came
Admission “A” 25,428 à 25,528 mm
(1,0011 à 1,0050 in)25,4 mm
(1,00 in)
“B” 21,034 à 21,134 mm
(0,8281 à 0,8320 in)21,0 mm
(0,83 in)
“C” 4,328 à 4,628 mm
(0,1704 à 0,1822 in)----
Echappement “A” 25,286 à 25,386 mm
(0,9955 à 0,9994 in)25,26 mm
(0,99 in)
“B” 21,047 à 21,147 mm
(0,8286 à 0,8326 in)21,017 mm
(0,83 in)
“C” 4,186 à 4,486 mm
(0,1648 à 0,1766 in)----
Limite de voile d’arbre à cames ---- 0,03 mm
(0,0012 in)
C
A
B