2000 YAMAHA TTR90 check engine light

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.

3 - 5
INSP
ADJ

ENGINE OIL LEVEL INSPECTION
1. Stand the motorcycle on a level surface.
NOTE:

l
When checking the oil level make sure that
the motorcycle is upright.
l
Place the motorcycle on a suitable stand.
WARNING

Never remove the oil tank cap just after
high speed operation. The heated oil could
spurt out causing danger. Wait until the oil
cools down to approximately 70 ˚C (158 ˚F).
2. Idle the engine more than 3 minutes
while keeping the motorcycle upright.
Then stop the engine and inspect the oil
level.
3. Remove:
l
Dipstick
1
4. Inspect:
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
oil level gauge 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 (10W30) or SAE
10W30 type SE/SF motor oil
At 5 ˚C (40 ˚F) or higher
õ
:
Yamalube 4 (20W40) or SAE
20W40 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 - 19
INSP
ADJ
ELECTRICAL/SPARK PLUG INSPECTION
EC370000
ELECTRICAL
EC371001
SPARK PLUG INSPECTION
1. Remove:
lSpark plug
2. Inspect:
lElectrode 1
Wear/damage ® Replace.
lInsulator color 2
Normal condition is a medium to light
tan color.
Distinctly different color ® Check the
engine condition.
NOTE:
When the engine runs for many hours at low
speeds, the spark plug insulator will become
sooty, even if the engine and carburetor are in
good operating condition.
3. Measure:
lPlug gap a
Use a wire gauge or thickness gauge.
Out of specification ® Regap.
4. Clean the plug with a spark plug cleaner
if necessary.
Spark plug gap:
0.6 ~ 0.7 mm (0.02 ~ 0.03 in)
Standard spark plug:
CR6HSA (NGK)
U20FSR-U (DENSO)
5. Tighten:
lSpark plug
NOTE:
lBefore installing a spark plug, clean the gas-
ket surface and plug surface.
lFinger-tighten a the spark plug before
torquing to specification b.
T R..13 Nm (1.3 m · kg, 9.4 ft · lb)

4 - 46
ENG

SHIFT FORK, SHIFT CAM AND TRANSMISSION
EC4H3000
REMOVAL POINTS
Shift fork, shift cam and transmission
1. Remove:
l
Shift forks
l
Shift cam
l
Drive axle assembly
l
Main axle assembly
NOTE:

l
Tap lightly on the transmission drive axle and
shift cam with a soft hammer to remove.
l
Remove assembly carefully. Note the posi-
tion of each part. Pay particular attention to
the location and direction of shift forks.
ASSEMBLY AND INSTALLATION
Transmission, shift cam shift fork
1. Install:
l
Main axle assembly
1

l
Drive axle assembly
2

2. Install:
l
Shift fork 1 “L”
1

l
Shift fork 2 “R”
2

l
Shift cam
3

l
Guide bar
4

NOTE:

The embossed marks on the shift forks should
face towards the right side of the engine and
be in the following sequence: “R”, “L”.
3. Check:
l
Shifter operation
l
Transmission operation
Unsmooth operation
®
Repair.