Yamaha YZF-R125 Service Manual: 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 probe gray "1"
- Negative tester probe gray/black "2"
b. Set the main switch to "ON".
c. Elevate the front wheel and slowly rotate it.
d. Measure the voltage of gray and gray/black.
With each full rotation of the front wheel, the voltage reading should cycle from 0 V to 5.0 V to 0 V to 5.0 V.
Checking the fuel sender
1. Drain the fuel from the fuel tank.
2. Check:
Fuel sender resistance
Out of specification → Replace the fuel
sender.
a. Connect the pocket tester ( ×
10) to the fuel
sender c ...
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.
Posi ...
Other materials:
Removing the lower bracket
1. Stand the vehicle on a level surface.
WARNINGSecurely support the vehicle so that there
is
no danger of it falling over.
2. Remove:
Upper ring nut
Rubber washer
Lower ring nut "1"
Lower bracket
NOTE:
Remove the lower ring nut with the steering nut
wrench "2".
...
Checking the front brake disc
1. Remove:
Front wheel
Refer to "FRONT WHEEL" on page 4-6.
2. Check:
Brake disc
Damage/galling Replace.
3. Measure:
Brake disc deflection
Out of specification Correct the
brake disc
deflection or replace the brake disc.
a. Place the vehicle on a suitable stand ...
Checking the lean angle sensor
1. Remove:
Lean angle sensor
2. Check:
Lean angle sensor output voltage
Out of specification Replace.
a. Connect the lean angle sensor to the wire
harness.
b. Connect the pocket tester (DC 20 V) to the
lean angle sensor coupler as shown.
Positive tester probe
yellow/green "1"
Neg ...