2001 YAMAHA YZ125LC transmission oil

2-13
SPECCABLE ROUTING DIAGRAM
EC240000
1Brake hose
2Fuel tank breather hose
3Cable guide
4Clamp
5“ENGINE STOP” button lead
6Throttle cable
7Air vent hose (right)
8Air vent hose (left)
9Transmission oil breather
hose
0Overflow hose
qRadiator breather hose
wCDI magneto lead
eYPVS breather hose
APass the fuel tank breather
hose between the handlebar
and tension bar, then insert
its end into the hole of the
number plate.
BPass the throttle cable and
“ENGINE STOP” button lead
into the cable guide. Align
with the cable guide the
front end of the tape on the
throttle cable.CClamp the throttle cable and
“ENGINE STOP” button lead
to the frame. With the clamp
ends downward, tighten the
throttle cable to the extent
that it moves smoothly.
DClamp the “ENGINE STOP”
button lead (where there is
no protector), wireharness and
throttle cable all together to the
frame. With the clamp ends
downward, pass the
wireharness on the outer side
of the chassis in relation to the
“ENGINE STOP” button lead.
EPass the air vent hose at
the rear of the throttle cable.
FPass the transmission oil
breather hose, air vent hoses
and overflow hose between
the frame and connecting rod.
GPass the radiator breather
hose and YPVS breather hose
outside the engine bracket
and inside the frame. Then
pass the radiator breather hose inside the YPVS
breather hose.
HClamp the radiater breather
hose and CDI magneto lead
on the rear of the down-tube.
IPass the radiater breather
hose and CDI magneto
lead between the frame and
radiator.
JAlign the top of the brake hose
neck with the brake hose
holder bottom.
KPass the brake hose in front
of the axle boss, then fit it
into the hose groove so that
the brake hose does not
contact the nut (wheel axle).
LFit the brake hose into the
guide on the protector.
MPass the throttle cable and
“ENGINE STOP” button lead
over the radiator hose.
NTighten the clamp with its
ends sideways as shown.
5MV-9-30-2B 6/19/00 1:14 PM Page 26

3-1
MAINTENANCE INTERVALS
INSP
ADJ
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
EC310051
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the required
maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in maintaining
and lubricating your machine, consult your Yamaha dealer.
Item Remarks
PISTON
Inspect and cleanllInspect crack
ReplacellRemove carbon
PISTON RING
InspectllCheck ring end gap
Replacell
PISTON PIN, SMALL END BEARING
Inspectl
Replacel
CYLINDER HEAD
Inspect and cleanllRemove carbon
RetightenllCheck gasket
CYLINDER
Inspect and cleanll
lInspect score marks
ReplaceInspect wear
YPVS
Inspect and cleanll
CLUTCHInspect housing, friction
Inspect and adjustllplate, clutch plate and
Replacelspring
TRANSMISSION
Replace oilllYamalube 4 (10W-30) or
InspectlSAE 10W-30 SE motor oil
Replace bearingl
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectlInspect wear
ROTOR NUT
Retightenll
MUFFLER
Inspectll
Cleanl
CRANK
Inspect and cleanll
CARBURETOR
Inspect, adjust and cleanll
SPARK PLUG
Inspect and cleanll
Replacel
DRIVE CHAIN Use chain lube
Lubricate, slack, alignmentllChain slack: 40~50 mm
Replacel(1.6~2.0 in)
After
break-
inEvery
raceEvery
thirdEvery
fifthAs re-
quired
3
5MV-9-30-3A 6/19/00 1:52 PM Page 2

3-4
PRE-OPERATION INSPECTION AND MAINTENANCE
INSP
ADJ
EC320000
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.
EC321000
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
Coolant Check that coolant is filled up to the radiator filler cap.
Check the cooling system for leakage.P3-5~9
Fuel Check that a fresh mixture of oil and gasoline is filled in
the fuel tank. Check the fuel line for leakage.P1-12
Transmission oil Check that the oil level is correct. Check the crankcase
for leakage.P3-12~14
Gear shifter and clutch Check that gears can be shifted correctly in order and
that the clutch operates smoothly.P3-9
Throttle grip/Housing Check that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and P3-10~11
housing, if necessary.
Brakes Check the play of front brake and effect of front and
rear brake.P3-17~23
Chain Check chain slack and alignment. Check that the chain
is lubricated properly.P3-24~26
Wheels Check for excessive wear and tire pressure. Check for
loose spokes and have no excessive play.P3-34~35
Steering Check that the handlebar can be turned smoothly and
have no excessive play.P3-35~36
Front forks and Check that they operate smoothly and there is no oil
rear shock absorber leakage.P3-26~33
Cables (wires) Check that the clutch and throttle cables move smooth-
ly. Check that they are not caught when the handlebars —
are turned or when the front forks travel up and down.
Muffler Check that the muffler is tightly mounted and has no
cracks.P3-15~16
Sprocket Check that the driven sprocket tightening bolt is
not loose.P3-24
Lubrication Check for smooth operation. Lubricate if necessary. P3-37
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P1-16
Lead connectors Check that the CDI magneto, CDI unit, and ignition coil
are connected tightly.P1-6
Settings Is the machine set suitably for the condition of the
racing course and weather or by taking into account the
P7-1~24
results of test runs before racing? Are inspection and
maintenance completely done?
5MV-9-30-3A 6/19/00 1:52 PM Page 14

3-12
INSP
ADJ
TRANSMISSION OIL LEVEL CHECK
3. Inspect:
9Air filter element
Damage ÕReplace.
4. Apply:
9Foam-air-filter oil or engine mixing oil
To the element.
NOTE:
Squeeze out the excess oil. Element should be
wet but not dripping.
5. Install:
9Filter guide 1
NOTE:
Align the projection aon filter guide with the
hole bin air filter element.
6. Apply:
9Lithium soap base grease
On the matching surface aon air filter ele-
ment.
7. Install:
9Air filter element 1
9Washer
9Fitting bolt
NOTE:
Align the projection aon filter guide with the
hole bin air filter case.
EC35H002
TRANSMISSION OIL LEVEL CHECK
1. Start the engine, warm it up for several min-
utes and wait for five minutes.
2. Place the machine on a level place and hold
it up on upright position by placing the suit-
able stand under the engine.
2 Nm (0.2 m•kg, 1.4 ft•lb)
5MV-9-30-3A 6/19/00 1:52 PM Page 32

3-13
INSP
ADJ
TRANSMISSION OIL REPLACEMENT
3. Check:
9Transmission oil level
EC35K002
TRANSMISSION OIL REPLACEMENT
1. Start the engine and warm it up for several
minutes and wait for five minute.
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.
Transmission oil level checking steps:
9Remove the oil check bolt 1.
9Inspect the oil level.
NOTE:
Be sure the machine is positioned straight
up when inspecting the oil level.
w
Never attempt to remove the oil check bolt
just after high speed operation. The heat-
ed oil could spout out, causing danger.
Wait until the oil cools down.
Oil flows out ÕOil level is correct.
Oil does not flow out ÕOil level is low.
Add transmission
oil until oil flows
out.
9Inspect the gasket (oil check bolt),
replace if damaged.
9Tighten the oil check bolt.
Recommended oil:
Yamalube 4 (10W-30) or SAE
10W-30 type SE motor oil
Oil check bolt:
10 Nm (1.0 m•kg, 7.2 ft•lb)
5MV-9-30-3A 6/19/00 1:52 PM Page 34

3-14
INSP
ADJ
PILOT AIR SCREW ADJUSTMENT
4. Remove:
9Oil drain bolt 1
9Oil filler cap 2
Drain the transmission oil.
5. Install:
9Aluminum washer
9Oil drain bolt 1
6. Fill:
9Transmission oil
7. Check:
9Oil leakage
8. Check:
9Transmission oil level
9. Install:
9Oil filler cap 2
EC35L002
PILOT AIR SCREW ADJUSTMENT
1. Adjust:
9Pilot air screw 1
Recommended oil:
Yamalube 4 (10W-30) or SAE
10W-30 type SE motor oil
Oil capacity
(periodic oil change):
0.65 L (0.57 Imp qt, 0.69 US qt)
Adjustment steps:
9Screw in the pilot air screw until it is
lightly seated.
9Back out by the specified number of
turns.
Pilot air screw:
1-1/4 turns out
*1-1/2 turns out
20 Nm (2.0 m•kg, 14 ft•lb)
*For EUROPE
5MV-9-30-3A 6/19/00 1:52 PM Page 36

4-30
ENGCLUTCH AND PRIMARY DRIVEN GEAR
Extent of removal Order Part name Q’ty Remarks
CLUTCH PLATE AND
FRICTION PLATE REMOVAL
Preparation for Drain the transmission oil.
Refer to “TRANSMISSION OIL REPLACE-
removalMENT“ section in the CHAPTER 3.
Bolt (brake pedal) Shift the brake pedal downward.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Screw (clutch spring) 5
3 Clutch spring 5
4 Pressure plate 1
5 Push rod 1
6 Plain washer 2
7 Bearing 1
8 Friction plate 8
9 Clutch plate 7
Extent of removal:1Clutch plate and friction plate removal
EC490000
CLUTCH AND PRIMARY DRIVEN GEAREC498000
CLUTCH PLATE AND FRICTION PLATE
1
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
5MV-9-30-4B 6/19/00 1:44 PM Page 26

4-34
ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC495000
ASSEMBLY AND INSTALLATION
EC495240
Clutch
1. Install:
9Plain washer [φ34 mm (1.34 in)] 1
9Spacer 2
9Bearing 3
9Primary driven gear 4
NOTE:
Apply the transmission oil on the spacer, bearing
and primary driven gear inner circumference.
2. Install:
9Plain washer [φ34 mm (1.34 in)] 1
9Clutch boss 2
3. Install:
9Lock washer 1
9Nut (clutch boss) 2
NOTE:
Use the clutch holding tool 3, 4to hold the
clutch boss.
å
For USA and CDN
∫
Except for USA and CDN
4. Bend the lock washer 1tab.
80 Nm (8.0 m•kg, 58 ft•lb)
Clutch holding tool:
YM-91042...............................3 3
90890-04086...........................4 4
å
∫
5MV-9-30-4B 1/7/04 5:29 PM Page 34