Yamaha YZF-R125 Service Manual: Checking the radiator fan motor
1. Check:
- Radiator fan motor Faulty/rough movement → Replace.
a. Disconnect the radiator fan motor coupler from the wire harness.
b. Connect the battery (DC 12 V) as shown.
- Positive tester probe → blue "1"
- Negative tester probe → black "2"
c. Measure the radiator fan motor movement.
Checking the speed sensor
1. Check:
Speed sensor output voltage
Out of specification → Replace.
a. Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness end) as
shown.
Positive tester pro ...
Checking the coolant temperature sensor
1. Remove:
Coolant temperature sensor
WARNING
Handle the coolant temperature sensor
with special care.
Never subject the coolant temperature sensor
to strong shocks. If t ...
Other materials:
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 driven gear
Pin "2"
NOTE:
When installing the inner rotor, align the pin "2"
in the oil pump sh ...
Intake air pressure sensor
1. Check:
Intake air pressure sensor output voltage
Out of specification Replace the throttle
body.
a. Connect the pocket tester (DC 20 V) to the
throttle body sensor assembly coupler as
shown.
Positive tester probe
pink/white "1"
Negative tester probe
gray/black "2"
...
Checking the timing chain and timing chain guide
1. Check:
Timing chain
Damage/stiffness Replace the
timing
chain and camshaft sprocket as a set.
2. Check:
Timing chain guide (intake side)
Damage/wear Replace.
Checking the oil strainer
1. Check:
Oil strainer
Damage Replace.
Contaminants Clean with solvent.
...