brake YAMAHA YZ250LC 2001 Manuale duso (in Italian)

2-15
CABLE ROUTING DIAGRAMSPEC
1Brake hose holder
2Master cylinder
3Brake hose
4Reservoir hose
5Hose guide
6Clamp
7High tension cord
8Ignition coil
9Clutch cable
0Cable guide
qGround lead
wRadiator breather hose
eCDI magneto lead
rThrottle cable
tCDI unit lead
y“ENGINE STOP” button lead
uFuel tank damper
iEngine bracket
APass the brake hose into the
brake hose holder.BIf the brake hose contacts the
spring (rear shock absorber),
correct its twist.
CInstall the brake hose so that its
pipe portion directs as shown
and lightly touches the projec-
tion on the master cylinder.
DPass the reservoir hose
between the brake hose and
swingarm bracket.
EPass the reservoir hose into the
hose guide.
FClamp the high tension cord,
throttle cable, TPS (throttle posi-
tion sensor) and solenoid valve
lead so that the high tension
cord does not contact the
engine bracket installation nuts.
G
Fasten the ground lead together
with the front installation portion
of the ingnition coil.
HPass the clutch cable into the
cable guide.
IPosition the CDI magneto lead
coupler between the radiators.
JInstall the brake hose to the
caliper with the paint on the pipe
facing the caliper and with the
pipe contacting the caliper pro-
jection.
KPass the radiator breather hose
between the frame and radiator
hose so that it is not kinked or
wedged.
LPass the throttle cable, CDI unit
lead, “ENGINE STOP” button
lead and clutch cable between
the fuel tank damper tube ends.
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2-16
CABLE ROUTING DIAGRAMSPEC
1Brake hose
2Master cylinder
3“ENGINE STOP” button lead
4“ENGINE STOP” button
5Throttle cable
6Clutch cable
7Clamp
8Cable guideAInstall the brake hose so that its pipe portion
dirrects as show and lightly touches the projection
on the master cylinder.
BPass the “ENGINE STOP” button lead in the middle
of the clutch holder.
CPass the clutch cable in front of the throttle cable.
DClamp the “ENGINE STOP” button lead to the han-
dlebar to 3 clicks.
EPass the brake hose in front of the number plate
and through the cable guide.
FCross the clutch cable and throttle cable over the
number plate mounting boss.
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INSP
ADJ
3-2
MAINTENANCE INTERVALS
3
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
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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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3-17
CHASSIS/BRAKE SYSTEM AIR BLEEDING
INSP
ADJ
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
w
Bleed the brake system if:
9The system has been disassembled.
9A brake hose has been loosened or removed.
9The brake fluid is very low.
9The brake operation is faulty.
A dangerous loss of braking performance may
occur if the brake system is not properly bleed.
1. Remove:
9Master cylinder cap
9Diaphragm
9Protector (rear brake)
2. Bleed:
9Brake fluid
Front
õRear
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube
2tightly to
the caliper bleed screw 1.
d. Place the other end of the tube into a
container.
e. Slowly apply the brake lever or pedal sev-
eral times.
f. Pull the lever in or push down on the ped-
al. Hold the lever or pedal in position.
g. Loosen the bleed screw and allow the
lever or pedal to travel towards its limit.
h. Tighten the bleed screw when the lever or
pedal limit has been reached; then re-
lease the lever or pedal.
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•lb)
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3-18
FRONT BRAKE ADJUSTMENT
INSP
ADJ
3. Install:
9Protector (rear brake)
9Diaphragm
9Master cylinder cap
EC362040
FRONT BRAKE ADJUSTMENT
1. Check:
9Brake lever position a
2. Adjust:
9Brake lever position
NOTE:
If bleeding is difficult, it may be necessary
to let the brake fluid system stabilize for a
few hours. Repeat the bleeding procedure
when the tiny bubbles in the system have
disappeared.
j. Add brake fluid to the level line on the
reservoir.
w
Check the operation of the brake after
bleeding the brake system.
Brake lever position a a
:
Standard position Extent of adjutment
95 mm (3.74 in)76 ~ 97 mm
(2.99 ~ 3.82 in)
Brake lever position adjustment steps:
9Loosen the locknut 1.
9Turn the adjusting bolt 2until the lever posi-
tion a is within specified position.
9Tighten the locknut.
cC
Be sure to tighten the locknut, as it will
cause poor brake performance.
Locknut:
5 Nm (0.5 m•kg, 3.6 ft•lb)
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3-19
REAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENTINSP
ADJ
EC365080
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
9Brake pad thickness a
Out of specification ÕReplace as a set.
2. Replace:
9Brake pad
Brake pad thickness a a
:
Standard
4.4 mm (0.17 in)
1.0 mm (0.04 in)
Brake pad replacement steps:
9Remove the pad pin plug 1.
EC364002
REAR BRAKE ADJUSTMENT
1. Check:
9Brake pedal height a
Out of specificationÕAdjust.
2. Adjust:
9Brake pedal height
Brake pedal height a a
:
5 mm (0.20 in)
Pedal height adjustment steps:
9Loosen the locknut 1.
9Turn the adjusting nut 2until the pedal
height ais within specified height.
9Tighten the locknut.
w
9Adjust the pedal height between the
maximum
and the minimum õ õ
as
shown. (In this adjustment the bolt 3 3
end b b
should protrude out of the lower
adjusting nut 4 4
but not be less than 2
mm (0.08 in) c c
away from the brake ped-
al 5 5
).
9After the pedal height adjustment, make
sure that the rear brake does not drag.
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3-20
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
9Loosen the pad pin 2.
9Remove the brake hose holder 3and
caliper 4from the front fork.
9Remove the pad pin and brake pads 5.
9Connect the transparent hose 6to the
bleed screw 7and 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 8and pad pin.
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
9Install the brake hose holder 9and caliper
0and tighten the pad pin q.
NOTE:
Fit the brake hose holder cut cover the pro-
jection
don the front fork and clamp the
brake hose.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•b)
Bolt (caliper):
23 Nm (2.3 m•kg, 17 ft•lb)
Pad pin:
18 Nm (1.8 m•kg, 13 ft•lb)
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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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