maintenance YAMAHA YZ125LC 2001 User Guide

2-9
SPECMAINTENANCE SPECIFICATIONS
NOTE:
1. First, tighten the ring nut approximately 38 Nm (3.8 m•kg, 27 ft•lb) by using the ring nut wrench,
then loosen the ring nut one turn.
2. Retighten the ring nut 7 Nm (0.7 m•kg, 5.1 ft•lb).
Part to be tightened Thread size Q'tyT ightening torqueNm m•kg ft•lb
Handle crown and outer tube M 8 ´1.25 4 23 2.3 17
Under bracket and outer tube M 8 ´1.25 4 20 2.0 14
Handle crown and steering shaft M24 ´1.0 1 145 14.5 105
Handlebar holder (upper) M 8 ´1.25 4 28 2.8 20
Steering ring nut M28 ´1.0 1 Refer to NOTE
Front fork and cap bolt M48 ´1.0 2 30 3.0 22
Front fork and base valve M30 ´1.0 2 55 5.5 40
Cap bolt and damper rod (front fork) M12 ´1.25 2 29 2.9 21
Bleed screw (front fork) and cap bolt M 5 ´0.8 2 1 0.1 0.7
Front fork and protector M 6 ´1.0 6 10 1.0 7.2
Cable guide (front brake hose) and guide stayM 5 ´0.8 1 4 0.4 2.9
Front fork and brake hose holder M 6 ´1.0 2 10 1.0 7.2
Front fork and hose cover M 8 ´1.25 1 16 1.6 11
Front fork and hose cover M 6 ´1.0 1 7 0.7 5.1
Throttle cable cap M 4 ´0.7 2 1 0.1 0.7
Front brake master cylinder and bracket M 6 ´ 1.0 2 9 0.9 6.5
Brake lever (bolt) M 6 ´1.0 1 6 0.6 4.3
(nut) M 6 ´1.0 1 6 0.6 4.3
Brake lever position locknut M 6 ´1.0 1 5 0.5 3.6
Clutch lever (bolt) M 6 ´1.0 1 2 0.2 1.4
Clutch lever holder M 5 ´0.8 2 4 0.4 2.9
Front brake master cylinder cap M 4 ´0.7 2 2 0.2 1.4
Front brake hose union bolt (master cylinder)M10 ´1.25 1 30 3.0 22
Front brake hose union bolt (caliper) M10 ´1.25 1 30 3.0 22
Front brake caliper and front fork M 8 ´1.25 2 23 2.3 17
Grip cap upper and lower M 6 ´1.0 2 4 0.4 2.9
Brake caliper (front and rear) and pad pin plugM10 ´1.0 1 3 0.3 2.2
Brake caliper (front and rear) and pad pin M10 ´1.0 1 18 1.8 13
Brake caliper (front and rear) and bleed screwM 8 ´1.25 1 6 0.6 4.3
Front wheel axle and nut M16 ´1.5 1 105 10.5 75
Front wheel axle holder M 8 ´1.25 4 23 2.3 17
Front brake disc and wheel hub M 6 ´1.0 6 12 1.2 8.7
Rear brake disc and wheel hub M 6 ´1.0 6 14 1.4 10
Brake pedal mounting M 8 ´1.25 1 26 2.6 19
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5MV-9-30-2A 6/19/00 1:15 PM Page 10

2-10
SPECMAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q'tyT ightening torqueNm m•kg ft•lb
Rear brake master cylinder and frame M 6 ´1.0 2 10 1.0 7.2
Rear brake reservoir tank and frame M 6 ´1.0 1 7 0.7 5.1
Rear brake hose union bolt (caliper) M10 ´1.25 1 30 3.0 22
Rear brake hose union bolt (master cylinder) M10 ´1.25 1 30 3.0 22
Rear wheel axle and nut M20 ´1.5 1 125 12.5 90
Nipple (spoke) – 72 3 0.3 2.2
Driven sprocket and wheel hub M 8 ´1.25 6 42 4.2 30
Disc cover and rear brake caliper M 6 ´1.0 2 7 0.7 5.1
Protector and rear brake caliper M 6 ´1.0 2 7 0.7 5.1
Engine mounting:
Engine and frame (front) M10 ´1.25 1 69 6.9 50
Engine and frame (lower) M10 ´1.25 1 69 6.9 50
Engine bracket and frame M 8 ´1.25 2 34 3.4 24
Engine bracket and engine M 8 ´1.25 1 34 3.4 24
Pivot shaft and nut M16 ´1.5 1 85 8.5 61
Relay arm and swingarm M14 ´1.5 1 80 8.0 58
Relay arm and connecting rod M14 ´1.5 1 80 8.0 58
Connecting rod and frame M14 ´1.5 1 80 8.0 58
Rear shock absorber and frame M10 ´1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 ´1.25 1 53 5.3 38
Rear frame and frame M 8 ´1.25 3 29 2.9 21
Swingarm and brake hose holder M 5 ´–4 4 0.4 2.9
Chain tensioner mounting M 8 ´1.25 2 19 1.9 13
Chain support and swingarm M 6 ´1.0 3 7 0.7 5.1
Seal guard and swingarm M 5 ´0.8 4 5 0.5 3.6
Fuel tank mounting M 6 ´1.0 2 10 1.0 7.2
Fuel tank and fuel cock M 6 ´1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M 6 ´1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M 6 ´1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M 6 ´1.0 4 7 0.7 5.1
Air scoop mounting M 6 ´1.0 8 3 0.3 2.2
Front fender mounting M 6 ´1.0 4 7 0.7 5.1
Rear fender mounting M 6 ´1.0 4 7 0.7 5.1
Side cover mounting M 6 ´1.0 4 7 0.7 5.1
Seat mounting M 6 ´1.0 2 7 0.7 5.1
Number plate M 6 ´1.0 1 7 0.7 5.1
NOTE:
s
s- marked portion shall be checked for torque tightening after break-in or before each race.
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2-11
SPECMAINTENANCE SPECIFICATIONS
EC212300
ELECTRICAL
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Stator M 6 ´1.0 3 8 0.8 5.8
Rotor M10 ´1.25 1 33 3.3 24
Ignition coil M 6 ´1.0 2 7 0.7 5.1
Item Standard Limit
Ignition system:
Ignition timing (B.T.D.C.) 32°/3000 r/min…
0.52 mm (0.020 in)…
Advancer type Electrical…
CDI:
Magneto-model/Manufacturer F4SS00/YAMAHA…
Source coil 1 resistance (color) 720~1,080 ½at 20°C (68°F)…
(Green/White-Black/Red)
Source coil 2 resistance (color) 44~66 ½at 20°C (68°F)…
(Black-Green/Blue)
Pickup coil resistance (color) 248~372 ½at 20°C (68°F)…
(White/Blue-White/Red)
CDI unit-model/Manufacturer 5MV-00/YAMAHA…
Ignition coil:
Model/Manufacturer 4SS-00/YAMAHA…
Minimum spark gap 6 mm (0.24 in)…
Primary winding resistance 0.14~0.20 ½at 20°C (68°F)…
Secondary winding resistance 6.7~10.1k½at 20°C (68°F)…
5MV-9-30-2A 6/19/00 1:15 PM Page 12

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
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3-2
MAINTENANCE INTERVALS
INSP
ADJ
Item Remarks
COOLING SYSTEM
Check coolant level and leakagell
Check radiator cap operationl
Replace coolantlEvery two years
Inspect hosesl
OUTSIDE NUTS AND BOLTS Refer to “STARTING
RetightenllAND BREAK-IN” section
in the CHAPTER 1.
AIR FILTER
Clean and lubricatellUse foam air-filter oil
Replacel
FRAME
Clean and inspectll
FUEL TANK, COCK
Clean and inspectll
BRAKES
Adjust lever position and pedal heightll
Lubricate pivot pointll
Check brake disc surfacell
Check fluid level and leakagell
Retighten brake disc bolts, caliper bolts,
ll
master cylinder bolts and union bolts
Replace padsl
Replace brake fluidlEvery one year
FRONT FORKS
Inspect and adjustll
Replace oilllSuspension oil “01”
Replace oil seall
FRONT FORK OIL SEAL AND DUST SEAL
Clean and lubellLithium base grease
REAR SHOCK ABSORBER
Inspect and adjustll
Lube ll
Molybdenum disulfide grease
Retightenll
CHAIN GUARD AND ROLLERS
Inspectll
SWINGARM
Inspect and retightenll
RELAY ARM, CONNECTING ROD
Inspect and lubellMolybdenum disulfide grease
STEERING HEAD
Inspect free play and retightenll
Clean and lubelLithium base grease
Replace bearingl
TIRE, WHEELS
Inspect air pressure, wheel run-out,
ll
tire wear and spoke looseness
Retighten sprocket boltll
Inspect bearingsl
Replace bearingsl
LubricatelLithium base grease
THROTTLE, CONTROL CABLE
Check routing and connectionllYamaha cable lube or
LubricatellSAE 10W-30 motor oil
After
break-
inEvery
raceEvery
thirdEvery
fifthAs re-
quired
3
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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?
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3-11
INSP
ADJ
AIR FILTER CLEANING
3. Install:
9Throttle cable cap
9Cap cover
EC35G040
AIR FILTER CLEANING
NOTE:
Proper air filter maintenance is the biggest key
to preventing premature engine wear and dam-
age.
cC
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
9Seat
9Fitting bolt 1
9Washer 2
9Air filter element 3
9Filter guide 4
2. Clean:
9Air filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent by
squeezing the element.
cC
Do not twist the element when squeezing
the element.
1 Nm (0.1 m•kg, 0.7 ft•lb)
5MV-9-30-3A 6/19/00 1:52 PM Page 30