YAMAHA T105 1998 Service Manual

*: It is recommended that these items be serviced by a Yamaha dealer.
**: Medium weight wheel bearing grease. (bearing type)
***: Lithium soap base grease. (bush type)
40
Check bearing assembly for looseness.
* Steering bearingCorrect if necessary. Moderately repack every228,000 km. **
* Front forksCheck operation/oil leakage. Repair if necessary.22* Rear shock absorberCheck operation/oil leakage. Repair if necessary.22
Drive chainCheck chain slack/alignment. Adjust if necessary.
EVERY 500 km
Clean and lube.
*
Fittings/FastenersCheck all chassis fitting and fasterners.
2222Correct if necessary.
* Centerstand and
Check operation. Repair if necessary.2222
sidestand
* BatteryCheck specific gravity. Check that the breather
22
pipe is working properly. Correct if necessary
INITIAL EVERY
ITEM REMARKS
500 km 2,000 km 4,000 km 8,000 km
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EAH48201*Engine oil
1. Oil level measurement
a. Place the motorcycle on the center-
stand. Warm up the engine for several
minutes.EUU03901NOTE:
Be sure the motorcycle is positioned
straight up when checking the oil level. A
slight tilt toward the side can result in false
readings.b. With the engine stopped, wait a few
minutes and then remove the oil level
gauge.
c. Wipe the oil level gauge off with a
clean rag and insert it in the filler hole
without screwing it in.
41
1Oil level gauge2Upper level3Lower level
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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)
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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
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Air filter
1. Remove the front panel and the
legshield by removing the screws.
2. Remove the air filter case fitting
screws and the filter case cover.
3. Remove the air filter element from its
case, and clean it with solvent. After
cleaning, remove the remaining sol-
vent by squeezing the element.
44
1Air filter case cover2Screw (4 pcs)1Air filter element
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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)
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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
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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
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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
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Before installing the spark plug, measure
the electrode gap with a wire thickness
gauge; adjust the gap to specification as
necessary.
When installing the plug, always clean the
gasket surface and use a new gasket. Wipe
off any grime from the threads and tighten
the spark plug to the specified torque.EUU03801NOTE:
If a torque wrench is not available when
you are installing a spark plug, a good esti-
mate of the correct torque is 1/4 to 1/2 turn
past finger tight. Have the spark plug
torqued to the correct value as soon as
possible with a torque wrench.
49
Spark plug gap:
0.6 ~ 0.7 mmSpark plug torque:
12.5 Nm (1.25 m•kg)
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