2003 YAMAHA YZ125LC maintenance

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)

5-53
CHASSWINGARM
EC573000
REMOVAL POINTS
EC573201
Bearing
1. Remove:
9Bearing 1
NOTE:
Remove the bearing by pressing its outer race.
EC574010
INSPECTION
Wash the bearings, bushes, collars, and covers in
a solvent.
EC574111
Swingarm
1. Inspect:
9Bearing 1
9Bush 2
Free play exists/Unsmooth revolution/Rust 
Replace bearing and bush as a set.
2. Inspect:
9Oil seal 3
Damage Replace.
EC574211
Relay arm
1. Inspect:
9Bearing (polylube bearing) 1
9Collar 2
Free play exists/Unsmooth revolution/Rust 
Replace bearing and collar as a set.
2. Inspect:
9Bearing (polylube bearing) 1
Loss of solid lubrication Replace.
9Oil seal 3
Damage Replace.
NOTE:
Polylube bearings, with solid lubrication, have
been adopted with the intent to make the needle
bearings, used in this model, maintenance free.
With polylube bearings, no grease nipple and
regular lubrication is necessary. However,
grease should be applied to all oil seals and col-
lars when removed or installed.

5-54
CHASSWINGARM
EC575000
ASSEMBLY AND INSTALLATION
EC575202
Bearing and oil seal
1. Install:
9Bearing 1
9Oil seal 2
To swingarm.
NOTE:
9Apply the molybdenum disulfide grease on the
bearing when installing.
9Install the bearing by pressing it on the side hav-
ing the manufacture's marks or numbers.
9First install the outer and then the inner bear-
ings to a specified depth from inside.
Installed depth of bearings:
Outer a a
: Zero mm (Zero in)
Inner b b
: 8.5 mm (0.33 in)
EC574311
Connecting rod
1. Inspect:
9Bearing (polylube bearing) 1
9Collar 2
Free play exists/Unsmooth revolution/Rust 
Replace bearing and collar as a set.
2. Inspect:
9Bearing (polylube bearing) 1
Loss of solid lubrication Replace.
9Oil seal 3
Damage Replace.
NOTE:
Polylube bearings, with solid lubrication, have
been adopted with the intent to make the needle
bearings, used in this model, maintenance free.
With polylube bearings, no grease nipple and
regular lubrication is necessary. However,
grease should be applied to all oil seals and col-
lars when removed or installed.