2007 YAMAHA YZ125LC engine oil

2-13
SPECCABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1“ENGINE STOP” button lead
2Throttle cable
3Clutch cable
4Ground lead
5High tension cord
6Clamp
7Air vent hose
8Radiator breather hose
9CDI magneto lead
0YPVS breather hose
qEngine bracket (right)
wEngine bracket (left)
eCrankcase breather hose
rOverflow hose
tConnector coverAPass the clutch cable on the
outside of the throttle cable and
“ENGINE STOP” button lead.
BAlign the throttle cable locating
tape with the cable guide.
CPass the throttle cable, clutch
cable and “ENGINE STOP”
button lead above the radiator
hose.
DInstall the ignition coil, side
core and ground lead together
to the frame. Take care to fas-
ten the ground lead so that its
terminal is within the indicated
range.
EClamp the throttle cable and
high tension cord to the frame.FClamp the clutch cable to the
left engine bracket. Clamp the
clutch cable below the posi-
tioning grommet.
GPass the air vent hose back of
the throttle cable.
HPass the air vent hose, over-
flow hose and crankcase
breather hose between the
frame and connecting rod.
IPass the radiator breather
hose and YPVS breather hose
outside the engine bracket and
inside the down tube. Then
pass the radiator breather
hose inside the YPVS breather
hose.
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2-15
SPECCABLE ROUTING DIAGRAM
1High tension cord
2“ENGINE STOP” button lead
3Ignition coil lead
4Clamp
5CDI unit
6CDI unit band
7Radiator breather hose
8CDI magneto lead
9Connector cover
0Throttle cable
qClutch cable
wCDI unit stay
APass the high tension cord to
the left of the radiator hose.
BUsing a plastic locking tie,
clamp the “ENGINE STOP”
button lead, ignition coil leadand CDI magneto lead togeth-
er with the clamp ends back-
ward and then cut off the tie
end.
CClamp to the frame the throttle
cable, clutch cable, ignition coil
lead and “ENGINE STOP” but-
ton lead. In so doing, clamp
the ignition coil lead and
“ENGINE STOP” button lead at
their protecting tubes. Tighten
the clamp so that the “ENGINE
STOP” button lead is not
pulled when the handlebar is
turned to the right and left.
DPass the CDI magneto lead
and radiator breather hose
between the frame and the
radiator(right).EClamp the CDI magneto lead
to the frame at its locating
tape.
FBring the connector cover into
contact with the coupler.
GLocate the clamp ends in the
arrowed range.
HInsert the CDI unit band until it
stops at the CDI unit stay.
IPass the CDI magneto lead
and radiator breather hose
between the frame and the
radiator hose so that they
come within the arrow-indicat-
ed range. Also take care so
that the CDI magneto lead
passes on the left of the radia-
tor breather hose.
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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.P3-35~37
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. P3-38
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
P7-1~23
results of test runs before racing? Are inspection and
maintenance completely done?
1C3-9-32-3A 5/1/06 9:01 AM Page 14

3-7
INSP
ADJ
RADIATOR CAP INSPECTION
cC
9Do not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
9Do not use water containing impurities
or oil.
7. Install:
9Radiator cap
Start the engine and warm it up for a sev-
eral minutes.
8. Check:
9Coolant level
Coolant level low Add coolant.
EC355000
RADIATOR CAP INSPECTION
1. Inspect:
9Seal (radiator cap) 1
9Valve and valve seat 2
Crack/Damage Replace.
Exist fur deposits 3Clean or replace.
Handling notes of coolant:
The coolant is harmful so it should be handled
with special care.
w
9When coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
9When coolant splashes to your clothes.
Quickly wash it away with water and then
with soap.
9When coolant is swallowed.
Quickly make him vomit and take him to
a doctor.
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3-12
INSP
ADJ
TRANSMISSION OIL LEVEL CHECK
3. Inspect:
9Air filter element
Damage Replace.
4. Apply:
9Foam-air-filter oil or equivalent 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)
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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 Oil level is correct.
Oil does not flow out Oil 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)
1C3-9-32-3A 5/1/06 9:02 AM Page 34

3-25
DRIVE CHAIN SLACK ADJUSTMENT
INSP
ADJ
EC36A061
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 Adjust
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:
48~58 mm (1.9~2.3 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
4. Check:
9Drive chain stiffness a
Clean and oil the chain and hold as
illustrated.
StiffReplace drive 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 Repair or
replace.
Drive chain slack adjustment steps:
9Loosen the axle nut 1and locknuts 2.
9Adjust chain slack by turning the
adjusters 3.
To tighten Turn adjuster 3 3
counter-
clockwise.
To loosen Turn 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)
Locknut:
19 Nm (1.9 m•kg, 13 ft•lb)
1C3-9-32-3B 4/29/06 11:37 AM Page 16