engine YAMAHA T105 1998 Owner's Manual

d. The oil level should be between the
maximum and minimum marks. If
the level is low, add sufficient oil to
raise it to the proper level.
2. Engine oil replacement
a. Warm up the engine for a few min-
utes.
b. Stop the engine. Place an oil pan
under the engine, and remove the
oil level gauge.
c. Remove the drain plug and drain the
oil.
d. Reinstall the drain plug (make sure it
is tight.)
42
q
1Drain plug
Tightening torque
Drain plug20 Nm (2.0 m•kg)
T105(E) O/M-2 9/11/01 11:17 AM Page 42 (1,1)

e. Fill engine with oil through the oil
level gauge hole.EUU47700cC9Do not put in any chemical additives or
use oils with a grade of “CD (for Diesel
engine)” or higher. Also, be sure not to
use oils labeled “ENERGY CONSERVING
II” or higher. Engine oil also lubricates
the clutch and additives could cause
clutch slippage.
9Be sure no foreign material enters the
crankcase.f. Start the engine and warm up for a
few minutes. While warming up check
for oil leakage. If oil leakage is found,
stop the engine immediately, and ask
a Yamaha dealer to check the cause.
43
Recommended oil:
See page 25
Oil quantity:
Total amount:
1.0 L
Periodic oil change:
0.8 L
T105(E) O/M-2 9/11/01 11:17 AM Page 43 (1,1)

4. Apply recommended oil to the entire
surface of the filter and squeeze out
the excess oil. The element should be
wet but not dripping.
5. Install the element in its case.cC9If oil is not applied to the element, the
engine damage may occur.
9Make sure the element is properly seat-
ed in the filter case.
9The engine should never be run without
the air filter element installed; excessive
piston and/or cylinder wear may result.
45
Recommended oil:
Yamalube 2 (2 stroke engine oil) or
Yamalube 4 (20W40)
T105(E) O/M-2 9/11/01 11:17 AM Page 45 (1,1)

EAH92200Throttle cable adjustmentEUU06400NOTE:
Before adjusting the throttle cable free
play, the engine idling speed should be ad-
justed.The throttle cable should have a specified
free play in the turning direction at the grip
flange. If the free play is incorrect, ask a
Yamaha dealer to make adjustment.
46
A. Free play: 3~7 mm
Free play:
3~7 mm
T105(E) O/M-3 9/11/01 11:17 AM Page 46 (1,1)

EAH92300Carburetor adjustment
The carburetor is a vital part of the engine
and requires very sophisticated adjust-
ment. Most adjustments should be left to a
Yamaha dealer who has the professional
knowledge and experience to do so.EAH92000Idle speed adjustment
1. Attach the tachometer.
2. Set the idle to the specified engine
speed by adjusting the throttle stop
screw; turn the screw in to increase
engine speed, and out to decrease en-
gine speed.
47
1Tachometer1Throttle stop screw
Standard idle speed:
1,400~1,600 r/min
T105(E) O/M-3 9/11/01 11:17 AM Page 47 (1,1)

EAH20304Spark plug inspection
The spark plug is an important engine
component and is easy to inspect. The con-
dition of the spark plug can indicate the
condition of the engine. The ideal color on
the white insulator around the center elec-
trode is a medium-to-light tan color for a
motorcycle that is being ridden normally.
Do not attempt to diagnose any problems
yourself. Instead, take the motorcycle to a
Yamaha dealer. You should periodically re-
move and inspect the spark plug because
heat and deposits will cause the spark plug
to slowly break down and erode. If elec-
trode erosion becomes excessive, or if car-
bon and other deposits are excessive, you
should replace the spark plug with the
specified plug.
48
Standard spark plug:
C6HSA/NGK or U20FS-U/
NIPPONDENSO
1Spark plug gap
T105(E) O/M-3 9/11/01 11:17 AM Page 48 (1,1)

EAK00000
CLEANING AND
STORAGE
EAK01302*A. CLEANING
Frequent, thorough cleaning of your mo-
torcycle will not only enhance its appear-
ance but will improve its general perfor-
mance and extend the useful life of many
components.
1. Rinse the dirt and degreaser off with a
garden hose.EUU34602cCExcessive hose pressure may cause water
seepage and deterioration of wheel bear-
ings, front fork, brakes, transmission seals
and electrical parts.2. After cleaning the motorcycle, dry all
surfaces with a chamois, clean towel,
or soft absorbent cloth.3. Dry the chain and lubricate it to pre-
vent rust.
4. Automotive-type wax may be applied
to all painted and chrome-plated sur-
faces. When finished, start the engine
and let it idle for several minutes.
EAK00700B. STORAGE
Long term storage (60 days or more) of
your motorcycle will require some preven-
tive procedures to guard against deteriora-
tion. After thoroughly cleaning the motor-
cycle, prepare for storage as follows:
1. Drain the fuel tank, fuel lines, and car-
buretor float bowl(s).
2. Remove the empty fuel tank, pour a
cup of SAE 10W30 or 20W40 motor oil
in the tank, shake the tank to coat the
inner surfaces thoroughly and drain
off the excess oil. Reinstall the tank.
64
T105(E) O/M-3 9/11/01 11:17 AM Page 64 (1,1)

66
Model
Dimensions:
Overall length 1,870 mm
Overall width 655 mm
Overall height 1,050 mm
Seat height 755 mm
Wheelbase 1,190 mm
Minimum ground clearance 130 mm
Basic weight:
With oil and full fuel tank 96 kg
Minimum turning radius: 1,800 mm
Engine:
Type Air cooled 4 stroke, SOHC
Cylinder arrangement Forward inclined single cylinder
Displacement 101.8 cm
3
Bore
×stroke 49.0
×54.0 mm
Compression ratio 9.0 : 1
Starting system Electric and kick starter
Lubrication system: Wet sump
SPECIFICATIONS
T105(E) O/M-3 9/11/01 11:17 AM Page 66 (1,1)

67
Model
Engine oil (4-cycle):
Type Yamalibe 4 (20W40) or equivalent
SAE 20W40 type SE motor oil
Capacity
Periodic oil change 0.8 L
Total amount 1.0 L
Air filter: Wet type element
Fuel:
Type Regular gasoline
Tank capacity 4.3 L
Reserve amount
Carburetor:
Type/manufacturer VM16SH/MIKUNI
T105(E) O/M-3 9/11/01 11:17 AM Page 67 (1,1)