Yamaha YZF-R125 Service Manual: Checking the oil pump
1. Check:
- Oil pump drive gear
- Oil pump driven gear
- Oil pump housing
- Oil pump housing cover
Cracks/damage/wear
Replace the
defective part(s).
2. Measure:
- Inner-rotor-to-outer-rotor-tip clearance "a"
- Outer-rotor-to-oil-pump-housing clearance "b"
- - Oil-pump-housing-to-inner-rotor-and-outerrotor clearance "c"
Out of specification Replace
the oil pump.
1. Inner rotor
2. Outer rotor
3. Oil pump housing 
3. Check:
Oil pump operation
Rough movement 
Repeat steps (1)
and
(2) or replace the defective part(s).
Oil pump
...
Assembling the oil pump
1. Lubricate:
Oil pump inner rotor
Oil pump outer rotor
Oil pump driven gear
(with the recommended lubricant)
2. Install:
Oil pump outer rotor
Oil pump inner rotor "1"
Oil pump dr ...
Other materials:
Checking and lubricating the cables
The operation of all control cables and
the condition of the cables should be
checked before each ride, and the cables
and cable ends should be lubricated
if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the out ...
General maintenance and lubrication chart
TIP
The air filter needs more frequent service if you are riding in
unusually wet or dusty areas.
Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
Every two years change the brake fluid.
Replace the brake hoses every four ye ...
Ignition circuit cut-off system
The ignition circuit cut-off system (comprising
the sidestand switch, clutch
switch and neutral switch) has the following
functions.
It prevents starting when the transmission
is in gear and the sidestand
is up, but the clutch lever is
not pulled.
It prevents starting when the t ...