wheel YAMAHA YZ125LC 2001 User Guide

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.
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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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3-21
REAR BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
3. Inspect:
9Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
9Brake lever operation
A softy or spongy feeling ÕBleed brake
system.
Refer to “BRAKE SYSTEM AIR BLEED-
ING” section.
EC366060
REAR BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
9Brake pad thickness a
Out of specification ÕReplace as a set.
2. Replace:
9Brake pad
9Install the pad pin plug w.
Pad pin plug:
3 Nm (0.3 m•kg, 2.2 ft•lb)
Brake pad thickness a a
:
Standard
6.4 mm (0.25 in)
1.0 mm (0.04 in)
Brake pad replacement steps:
9Remove the protector 1and pad pin plug
2.
9Loosen the pad pin 3.
9Remove the rear wheel 4and caliper 5.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.
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3-22
REAR BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
9Remove the pad pin 6and brake pads 7.
9Connect the transparent hose 8to the
bleed screw 9and place the suitable con-
tainer under its end.
9Loosen the bleed screw and push the
caliper piston in.
cC
Do not reuse the drained brake fluid.
9Tighten the bleed screw.
9Install the brake pads 0and pad pin q.
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
9Install the caliper wand rear wheel e.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.
9Tighten the pad pin r.
9Install the pad pin plug tand protector y.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•lb)
Pad pin:
18 Nm (1.8 m•kg, 13 ft•lb)
Pad pin plug:
3 Nm (0.3 m•kg, 2.2 ft•lb)
Bolt (protector):
7 Nm (0.7 m•kg, 5.1 ft•lb)
3. Inspect:
9Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
9Brake pedal operation
A softy or spongy feeling ÕBleed brake
system.
Refer to “BRAKE SYSTEM AIR BLEEDING”
section.
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3-25
DRIVE CHAIN SLACK ADJUSTMENT
INSP
ADJ
EC36A060
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the suit-
able stand under the engine.
2. Check:
9Drive chain slack a
Above the seal guard installation bolt.
Out of specification ÕAdjust
NOTE:
Before checking and/or adjusting, rotate the rear
wheel through several revolutions and check the
slack several times to find the tightest point. Check
and/or adjust chain slack with rear wheel in this
“tight chain” position.
Drive chain slack:
40~50 mm (1.6~2.0 in)
Drive chain lubricant:
SAE 10W-30 motor oil or suitable
chain lubricants
5. Install:
9Drive chain 1
9Joint 2
9Master link clip 3
cC
Be sure to install the master link clip to the
direction as shown.
aTurning direction
6. Lubricate:
9Drive chain
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3-26
FRONT FORK INSPECTION
INSP
ADJ
3. Adjust:
9Drive chain slack
EC36C000
FRONT FORK INSPECTION
1. Inspect:
9Front fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage ÕRepair or
replace.
Drive chain slack adjustment steps:
9Loosen the axle nut 1and locknuts 2.
9Adjust chain slack by turning the
adjusters 3.
To tighten ÕTurn adjuster 3 3
counter-
clockwise.
To loosen ÕTurn adjuster 3 3
clockwise
and push wheel forward.
9Turn each adjuster exactly the same amount
to maintain correct axle alignment. (There are
marks aon each side of chain puller align-
ment.)
NOTE:
Turn the adjuster so that the chain is in line
with the sprocket, as viewed from the rear.
cC
Too small chain slack will overload the
engine and other vital parts; keep the
slack within the specified limits.
9Tighten the axle nut while pushing down the
drive chain.
9Tighten the locknuts.
Axle nut:
125 Nm (12.5 m•kg, 90 ft•lb)
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3-30
REAR SHOCK ABSORBER SPRING PRELOAD
ADJUSTMENTINSP
ADJ
EC36M013
REAR SHOCK ABSORBER SPRING
PRELOAD ADJUSTMENT
1. Elevate the rear wheel by placing the suit-
able stand under the engine.
2. Remove:
9Rear frame
3. Loosen:
9Locknut 1
4. Adjust:
9Spring preload
By turning the adjuster 2.
NOTE:
9Be sure to remove all dirt and mud from around
the locknut and adjuster before
adjustment.
9The length of the spring (installed) changes 1.5
mm (0.06 in) per turn of the adjuster.
cC
Never attempt to turn the adjuster beyond
the maximum or minimum setting.
5. Tighten:
9Locknut
6. Install:
9Rear frame
Stiffer ÕIncrease the spring preload.
(Turn the adjuster 2 2
in.)
Softer ÕDecrease the spring pre-
load. (Turn the adjuster 2 2
out.)
Extent of adjustment
242~260 mm
(9.53~10.24 in)
*257~275 mm
(10.12~10.83 in)
Spring length (installed) a a
:
Standard length
248 mm (9.76 in)
*262 mm (10.31 in)
*For EUROPE
29 Nm (2.9 m•kg, 21 ft•lb)
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3-34
TIRE PRESSURE CHECK/SPOKES INSPECTION AND
TIGHTENING/WHEEL INSPECTIONINSP
ADJ
EC36Q000
TIRE PRESSURE CHECK
1. Measure:
9Tire pressure
Out of specification ÕAdjust.
NOTE:
9Check the tire while it is cold.
9Loose bead stoppers allow the tire to slip off its
position on the rim when the tire pressure is
low.
9A tilted tire valve stem indicates that the tire
slips off its position on the rim.
9If the tire valve stem is found tilted, the tire is
considered to be slipping off its position.
Correct the tire position.
EC36S002
SPOKES INSPECTION AND TIGHTENING
1. Inspect:
9Spokes 1
Bend/Damage ÕReplace.
Loose spoke ÕRetighten.
2. Tighten:
9Spokes
NOTE:
Be sure to retighten these spokes before and af-
ter break-in. After a practice or a race check
spokes for looseness.
EC36T000
WHEEL INSPECTION
1. Inspect:
9Wheel runout
Elevate the wheel and turn it.
Abnormal runout ÕReplace.
Standard tire pressure:
100 kPa (1.0 kg/cm
2, 15 psi)
3 Nm (0.3 m•kg, 2.2 ft•lb)
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3-35
STEERING HEAD INSPECTION AND ADJUSTMENT
INSP
ADJ
2. Inspect:
9Bearing free play
Exist play ÕReplace.
EC36U013
STEERING HEAD INSPECTION AND
ADJUSTMENT
1. Elevate the front wheel by placing a suitable
stand under the engine.
2. Check:
9Steering shaft
Grasp the bottom of the forks and gently
rock the fork assembly back and forth.
Free play ÕAdjust steering head.
3. Check:
9Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action ÕAdjust steering ring
nut.
4. Adjust:
9Steering ring nut
Steering ring nut adjustment steps:
9Remove the number plate.
9Remove the handlebar and handle crown.
9Loosen the ring nut 1using the ring nut
wrench 2.
9Tighten the ring nut 3using ring nut wrench
4.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
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