engine oil YAMAHA TTR90 2001 User Guide

3 - 2
INSP
ADJ

PRE-OPERATION INSPECTION AND MAINTENANCE
*: Since these items requires special tools data and technical skills, they should be serviced.
*
1

: For USA
SERVICE NOTES:

No. 1. DRIVE CHAIN: In addition to tension and alignment, chain must be lubricated every
0.5 ~ 1.0 hour. If unit is subjected to extremely hard usage and wet weather riding, chain
must be checked constantly. See “Lubrication Intervals” for additional details.
No. 2. AIR FILTER: Remove and clean filter every 20 ~ 40 hours.
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
* Chassis fastenersMake sure that all nuts, bolts and screws are
properly tightened.
Tighten if necessary.
SidestandCheck operation.
Lubricate and repair if necessary.
* Spark arrester
*
1

Clean.
* Front forkCheck operation and for oil leakage.
Correct accordingly.
*Rear shock
absorber assemblyCheck operation and shock absorber for oil
leakage.
Replace shock absorber assembly if necessary.
Item Routine Page
Brake Check operation/adjustment. P3-11
Engine oil Change oil as required. P3-5 ~ 7
Drive chain Check alignment/adjustment/lubrication. P3-12
Spark plug Check color/condition. P3-19
Throttle Check for proper throttle cable operation. P3-3
Air filter Foam type – must be clean and damp oil always P3-3 ~ 4
Wheels and tires Check pressure/runout/spoke tightness/bead stopper/axle nuts. P3-15 ~ 17
Fittings/fasteners Check all – tighten as necessary. P2-13Dealer
NoteItem Checks and maintenance jobsInitial Every
10 hours
(1 month)60 hours
(6 months)120 hours
(12 months)
3

3 - 4
INSP
ADJ

AIR FILTER CLEANING
1. Install:
l
Air scoop (right)
1

2. Install:
l
Air filter case cover
1

3. Clean:
l
Air filter element
Clean them with solvent.
NOTE:

After cleaning, remove the remaining solvent
by squeezing the element.
CAUTION:

l
Do not twist the element when squeezing
the element.
l
Leaving too much of solvent in the ele-
ment may result in poor starting.
4. Inspect:
l
Air filter element
Damage
®
Replace.
5. Apply:
l
Foam-air-filter oil or engine mixing oil
To the element.
NOTE:

Squeeze out the excess oil. Element should
be wet but not dripping.
6. Install:
l
Air filter element
1

NOTE:

Align the projection
a
on the air filter case with
the hole
b
in the air filter element.
7. Install:
l
Air filter case cover
8. Install:
l
Air scoop (right)

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:
l
Dipstick
1
4. Check:
l
Oil 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:

l
Do not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
l
Do 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 oil
010 30 50 70
90110
130
-20
-10 010
20 30 40
50

õ
˚C˚F

ENGINE OIL LEVEL INSPECTION

3 - 6
INSP
ADJ

ENGINE OIL REPLACEMENT
(Except for USA and CDN)
CAUTION:

l
Do not add any chemical additives or use
oils with a grade of CD
a
or higher.
l
Do not use oils labeled “ENERGY CON-
SERVING II”
b
or higher. Engine oil also
lubricates the clutch and additives could
cause clutch slippage.
l
Do not allow foreign materials to enter the
crankcase.
5. Install:
l
Dipstick
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:
l
Dipstick
1

l
Drain 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:
l
Gasket
l
Drain bolt
New
T R..20 Nm (2.0 m · kg, 14 ft · lb)

6. Fill:
l
Crankcase
Oil quantity:
Periodic oil change:
0.8 L (0.70 Imp qt, 0.85 US qt)
7. Install:
l
Dipstick
8. Inspect:
l
Engine (for oil leaks)
l
Oil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”.
PILOT AIR SCREW ADJUSTMENT
1. Adjust:
l
Pilot air screw
1

Adjusting steps:
l
Screw in the pilot air screw until it is lightly
seated.
l
Back out by the specified number of turns.
Pilot air screw:
1-3/4 turns out

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.

4 - 11
ENG

CYLINDER HEAD
4. Remove:
l
Cylinder head
NOTE:

l
Loosen the bolts and nuts in their proper
loosening sequence.
l
Start by loosening each bolt and nut 1/2 turn
until all are loose.
ASSEMBLY AND INSTALLATION
1. Install:
l
Cylinder head
2. Tighten:
l
Nuts
l
Bolts
NOTE:

l
Apply the engine oil on the contact surfaces
of the nuts, bolts and copper washers.
l
Follow 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:
l
Camshaft sprocket
1

Installation steps:
l
Turn the crankshaft counterclockwise until
the “I” mark
a
on the rotor is aligned with
the stationary pointer
b
on the crankcase
cover.
l
Align the “I” mark
c
on the camshaft
sprocket with the stationary pointer
d
on
the cylinder head.
l
Fit 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

4 - 25
ENG

CYLINDER AND PISTON
Piston pin
1. Inspect:
l
Piston pin
Blue discoloration/grooves
®

Replace, then inspect the lubrication
system.
2. Measure:
l
Piston pin outside diameter
l
Piston pin bore inside diameter
Measurement steps:
l
Measure the piston pin outside diameter
a
.
If out of specification, replace the piston
pin
Outside diameter (piston pin):
12.996 ~ 13.000 mm
(0.5117 ~ 0.5118 in)
:12.976 mm (0.5109 in)
l
Measure the piston inside diameter
b
.
If out of specification, replace the piston.
Inside diameter (piston):
13.002 ~ 13.013 mm
(0.5119 ~ 0.5123 in)
: 13.045 mm (0.5136 in)
ASSEMBLY AND INSTALLATION
Piston
1. Install:
l
Piston rings
(onto the piston)
NOTE:

l
Be sure to install the piston rings so that the
manufacturer’s marks or numbers are
located on the upper side of the rings.
l
Lubricate the piston and piston rings liberally
with engine oil.

4 - 26
ENG

CYLINDER AND PISTON
2. Position:
l
Top ring
l
2nd ring
l
Oil ring
Offset the piston ring end gaps as
shown.
a
Top ring end
b
Oil ring end (lower)
c
Oil ring end (upper)
d
2nd ring end
3. Install:
l
Piston
1

l
Piston pin
2
lPiston pin clips 3
NOTE:
lApply engine oil onto the piston pin, piston
ring and piston.
lBe sure that the arrow mark a on the piston
points to the exhaust side of the engine.
lBefore installing the piston pin clip, cover the
crankcase with a clean rag to prevent the
piston pin clip from falling into the crankcase.
4. Lubricate:
lPiston
lPiston rings
lCylinder
NOTE:
Apply a liberal coating of engine oil.
New
Cylinder
1. Install:
lDowel pins
lGasket
lCylinder 1
NOTE:
Install the cylinder with one hand while com-
pressing the piston rings with the other hand.
CAUTION:
lBe careful not to damage the timing chain
damper during installation.
lPass the timing chain through the timing
chain cavity.
New