2002 YAMAHA TTR90 oil

3 - 5
INSP
ADJ
ENGINE OIL LEVEL INSPECTION
1. Start the engine, warm it up for several
minutes and wait for five minutes.
2. Place the machine on a level place and
hold it up on upright position by placing
the suitable stand under the engine.
3. Remove:
lDipstick 1
4. Check:
lOil level
Oil level should be between maximum
a and minimum b marks.
Oil level is low ® Add oil to proper
level.
NOTE:
When inspecting the oil level, do not screw the
dipstick into the oil tank. Insert the gauge
lightly.
(For USA and CDN)
CAUTION:
lDo not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
lDo not allow foreign material to enter the
crankcase.
Recommended oil:
At –10 ˚C (10 ˚F) or higher :
Yamalube 4 (10W-30) or SAE
10W-30 type SE/SF motor oil
At 5 ˚C (40 ˚F) or higher õ:
Yamalube 4 (20W-40) or SAE
20W-40 type SE/SF motor oil010 30 50 70
90110
130
-20
-10010
20 30 40
50

õ
˚C˚F
ENGINE OIL LEVEL INSPECTION

3 - 6
INSP
ADJ
ENGINE OIL REPLACEMENT
(Except for USA and CDN)
CAUTION:
lDo not add any chemical additives or use
oils with a grade of CD a or higher.
lDo not use oils labeled “ENERGY CON-
SERVING II” b or higher. Engine oil also
lubricates the clutch and additives could
cause clutch slippage.
lDo not allow foreign materials to enter the
crankcase.
5. Install:
lDipstick
6. Start the engine and let it warm up for
several minutes.
7. Turn off the engine and inspect the oil
level once again.
NOTE:
Wait a few minutes until the oil settles before
inspecting the oil level.
ENGINE OIL REPLACEMENT
1. Start the engine and warm it up for sev-
eral minutes and wait for five minutes.
2. Place the machine on a level place and
hold it on upright position by placing the
suitable stand under the engine.
3. Place a suitable container under the
engine.
4. Remove:
lDipstick 1
lDrain bolt (with gasket) 2
Drain the crankcase of its oil.
Recommended oil:
Refer to the following chart for
selection of oils which are suited
to the atmospheric temperatures.
Recommended engine oil classi-
fication:
API STANDARD:
API “SE/SF” or higher grade
(Designed primarily for motor-
cycles)
a
b

3 - 7
INSP
ADJ
PILOT AIR SCREW ADJUSTMENT
5. Install:
lGasket
lDrain bolt
New
T R..20 Nm (2.0 m · kg, 14 ft · lb)
6. Fill:
lCrankcase
Oil quantity:
Periodic oil change:
0.8 L (0.70 Imp qt, 0.85 US qt)
7. Install:
lDipstick
8. Inspect:
lEngine (for oil leaks)
lOil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”.
PILOT AIR SCREW ADJUSTMENT
1. Adjust:
lPilot air screw 1
Adjusting steps:
lScrew in the pilot air screw until it is lightly
seated.
lBack out by the specified number of turns.
Pilot air screw:
1-3/4 turns out

INSP
ADJNETTOYAGE DU PARE-ETINCELLES (pour les USA)
FUNKENLÖSCHER REINIGEN (Nur USA)
6. Montieren:
lKipphebeldeckel (Einlaßseite) 1
lO-Ringe 2
7. Montieren:
lKipphebeldeckel (Auslaßseite)
lO-Ringe
lZündkerze
lSchwungrad-Abdeckschraube
lKurbelwellenendabdeckung
8. Montieren:
lLuftfiltergehäuse
lLufthutze (rechts)
FUNKENLÖSCHER REINIGEN (Nur USA)
WARNUNG
lSicherstellen, daß Krümmer und Schall-
dämpfer abgekühlt sind, bevor der Fun-
kenlöscher gereinigt wird.
lMotor beim Reinigen der Auspuffanlage
nicht starten.
1. Demontieren:
lSchraube (Auspuffendrohr) 1
2. Demontieren:
lAuspuffendrohr 2
Das Auspuffendrohr aus dem Schall-
dämpfer ziehen.
3. Reinigen:
lFunkenlöscher
Kohlenstoffablagerungen mit einer
Drahtbürste vom Funkenfängerteil an
der Innenseite des Schalldämpfers 3
entfernen.
Das Auspuffendrohr leicht anklopfen,
und die Kohlenstoffablagerungen vom
Außenteil a des Auspuffendrohrs ent-
fernen.
4. Montieren:
lAuspuffendrohr
Das Auspuffendrohr in den Schall-
dämpfer setzen, und das Schrauben-
loch ausrichten.
lSchraube (Auspuffendrohr)
T R..18 Nm (1,8 m · kg)
New
T R..18 Nm (1,8 m · kg)
New
T R..13 Nm (1,3 m · kg)
T R..7 Nm (0,7 m · kg)
T R..7 Nm (0,7 m · kg)
T R..7 Nm (0,7 m · kg)
6. Installer:
lCache de poussoir (côté admission) 1
lJoint torque 2
7. Installer:
lCache de poussoir (côté échappement)
lJoint torque
lBougie
lBouchon de distribution
lCache d’extrémit de vilebrequin
8. Installer:
lBoîtier de filtre à air
lCarénage de prise d’air (droit)
T R..18 Nm (1,8 m · kg, 13 ft · lb)
New
T R..18 Nm (1,8 m · kg, 13 ft · lb)
New
T R..13 Nm (1,3 m · kg, 9,4 ft · lb)
T R..7 Nm (0,7 m · kg, 5,1 ft · lb)
T R..7 Nm (0,7 m · kg, 5,1 ft · lb)
NETTOYAGE DU PARE-ETINCELLES
(pour les USA)
AVERTISSEMENT
lS’assurer que le tuyau et pot d’échappement
sont froids avant d’effectuer le nettoyage du
pare-étincelles.
lNe pas mettre le moteur en marche pendant le
nettoyage du système d’échappement.
1. Déposer:
lBoulon (chicane) 1
2. Déposer:
lChicane 2
Sortir la chicane du pot d’échappement.
3. Nettoyer:
lPare-étincelles
Utiliser une brosse à poils métalliques pour
nettoyer les dépôts de calamine de la partie
pare-étincelles de la surface intérieure du
pot d’échappement 3.
Tapoter légèrement la chicane et nettoyer
les dépôts de calamine de la surface exté-
rieure a de la chicane.
4. Installer:
lChicane
Insérer la chicane dans le pot d’échappement
et aligner l’orifice du boulon.
lBoulon (chicane)
T R..7 Nm (0,7 m · kg, 5,1 ft · lb)
3 - 10

3 - 13
INSP
ADJFRONT FORK INSPECTION/REAR SHOCK ABSORBER INSPECTION/
REAR SHOCK ABSORBER SPRING PRELOAD ADJUSTMENT
lTighten the wheel axle nut while pushing
down the drive chain.
T R..
Axle nut:
60 Nm (6.0 m • kg, 43 ft • lb)
EC36C000
FRONT FORK INSPECTION
1. Inspect:
lFront fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage ® Repair
or replace.
EC36K000
REAR SHOCK ABSORBER INSPECTION
1. Inspect:
lSwingarm smooth action
Abnormal noise/unsmooth action ®
Grease the pivoting points or repair the
pivoting points.
Damage/oil leakage ® Replace.
REAR SHOCK ABSORBER SPRING
PRELOAD ADJUSTMENT
1. Elevate the rear wheel by placing the
suitable stand under the engine.
2. Remove:
lRear shock absorber
Refer to “SWINGARM” section in the
CHAPTER 5.
3. Remove:
lSpring guide 1
NOTE:
While compressing the spring, remove the
spring guide.

3 - 18
INSP
ADJ
LUBRICATION
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Brake lever pivot
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Brake cable endUse Yamaha cable lube or equivalent on these
areas.
õUse SAE 10W-30 motor oil or suitable chain
lubricants.
‚Lubricate the following areas with high quality,
lightweight lithium-soap base grease.
AAA
AAB
CC
78

4 - 11
ENGCYLINDER HEAD
4. Remove:
lCylinder head
NOTE:
lLoosen the bolts and nuts in their proper
loosening sequence.
lStart by loosening each bolt and nut 1/2 turn
until all are loose.
ASSEMBLY AND INSTALLATION
1. Install:
lCylinder head
2. Tighten:
lNuts
lBolts
NOTE:
lApply the engine oil on the contact surfaces
of the nuts, bolts and copper washers.
lFollow the numerical order shown in the illus-
tration. Tighten the bolts and nuts in two
stages.
T R..22 Nm (2.2 m · kg, 16 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
3. Install:
lCamshaft sprocket 1
Installation steps:
lTurn the crankshaft counterclockwise until
the “I” mark a on the rotor is aligned with
the stationary pointer b on the crankcase
cover.
lAlign the “I” mark c on the camshaft
sprocket with the stationary pointer d on
the cylinder head.
lFit the timing chain 2 onto camshaft
sprocket and install the camshaft sprocket
on the camshaft.
NOTE:
When installing the camshaft sprocket, keep
the timing chain as tense as possible on the
exhaust side.

4 - 14
ENGCAMSHAFT AND ROCKER ARMS
REMOVAL POINTS
Rocker arm shaft
1. Remove:
lRocker arm shafts
NOTE:
Use a slide hammer bolt 1 and weight 2 to
slide out the rocker arm shafts.
Slide hammer set:
YU-1083-A
Slide hammer bolt:
90890-01085
Weight:
90890-01084
INSPECTION
Camshaft
1. Measure:
lCam lobes length a and b
Out of specification ® Replace.
Cam lobes length limit:
Intake:
a 25.328 mm (0.9972 in)
b 20.934 mm (0.8242 in)
Exhaust:
a 25.186 mm (0.9916 in)
b 20.947 mm (0.8247 in)
ASSEMBLY AND INSTALLATION
1. Apply:
lMolybdenum disulfide oil
(onto the camshaft cam lobe)
lEngine oil
(onto the camshaft bearing)
2. Install:
lCamshaft 1