2002 YAMAHA YZ125LC key

EC080000
HOW TO USE
THIS MANUAL
EC081000
PARTICULARLY IMPORTANT IN
FORMATION
Q
The Safety Alert Symbol means ATTENTION!
BECOME ALERT! YOUR SAFETY IS IN-
VOLVED!
w
Failure to follow WARNING instructions could re-
sult in severe injury or death to the machine op-
erator, a bystander, or a person inspecting or re-
pairing the machine.
cC
A CAUTION indicates special precautions that
must be taken to avoid damage to the machine.
NOTE:
A NOTE provides key information to make pro-
cedures easier or clearer.
EC082000
FINDING THE REQUIRED PAGE
1. This manual consists of seven chapters;
“General Information”, “Specifications”,
“Regular inspection and adjustments”,
“Engine”, “Chassis”, “Electrical” and
“Tuning”.
2. The table of contents is at the beginning of
the manual. Look over the general layout of
the book before finding then required chap-
ter and item.
Bend the book at its edge, as shown, to find
the required fore edge symbol mark and go
to a page for required item and description.
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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)
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4-53
ENGCDI MAGNETO
Extent of removal Order Part name Q’ty Remarks
CDI MAGNETO REMOVAL
Preparation for Seat and fuel tank Refer to “SEAT, FUEL TANK AND
removal SIDE COVERS” section.
Bolt [Radiator (left)] Refer to “RADIATOR” section.
Disconnect the CDI magneto lead.
1 Crankcase cover (left) 1
2 Nut (rotor) 1 Use special tool.
3 Rotor 1 Refer to “REMOVAL POINTS”.
4 Stator 1
5 Woodruff key 1
EC4L0000
CDI MAGNETO
1
Extent of removal:1CDI magneto removal



8 Nm (0.8 m•kg, 5.8 ft•lb)
33 Nm (3.3 m•kg, 24 ft•lb)
5 Nm (0.5 m•kg, 3.6 ft•lb)
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4-54
ENGCDI MAGNETO
EC4L3000
REMOVAL POINTS
EC4L3102
Rotor
1. Remove:
9Nut (rotor) 1
9Plain washer 2
Use the rotor holding tool 3.
2. Remove:
9Rotor 1
Use the flywheel puller 2.
NOTE:
When installing the flywheel puller, turn it coun-
terclockwise.
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
9Rotor inner surface a
9Stator outer surface b
Damage Inspect the crankshaft runout
and crankshaft bearing.
If necessary, replace CDI magneto and/or
stator.
EC4L4200
Woodruff key
1. Inspect:
9Woodruff key 1
Damage Replace.
EC4L5000
ASSEMBLY AND INSTALLATION
EC4L5172
CDI magneto
1. Install:
9Stator 1
9Screw (stator) 2
NOTE:
Temporarily tighten the screw (stator) at this
point.
Rotor holding tool:
YU-1235/90890-01235
Flywheel puller:
YM-1189/90890-01189
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4-55
ENGCDI MAGNETO
2. Install:
9Woodruff key 1
9Rotor 2
NOTE:
9Clean the tapered portions of the crankshaft
and rotor.
9When installing the woodruff key, make sure
that its flat surface ais in parallel with the
crankshaft center line b.
9When installing the rotor, align the keyway c
of the rotor with the woodruff key.
3. Install:
9Plain washer 1
9Nut (rotor) 2
Use the rotor holding tool 3.
4. Adjust:
9Ignition timing
Refer to “IGNITION TIMING CHECK” sec-
tion in the CHAPTER 3.
5. Tighten:
9Screw (stator) 1
6. Check:
9Ignition timing
Re-check the ignition timing.
33 Nm (3.3 m•kg, 24 ft•lb)
Rotor holding tool:
YU-1235/90890-01235
8 Nm (0.8 m•kg, 5.8 ft•lb)
Ignition timing (B.T.D.C.):
0.52 mm (0.020 in)
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