Yamaha YZF-R125 Service Manual: 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"
Negative tester probe 
gray/black "2"
c. Set the main switch to "ON".
d. Tilt the lean angle sensor to 65.
e. Measure the lean angle sensor output voltage.
Checking the crankshaft position sensor
1. Disconnect:
Crankshaft position sensor coupler
(from the wire harness)
2. Check:
Crankshaft position sensor resistance
Out of specification Replace
the crankshaft
position senso ...
Checking the starter motor operation
1. Check:
Starter motor operation
Does not operate → Perform the electric
starting system troubleshooting, starting with
step 4.
Refer to "TROUBLESHOOTING" on page
8-9.
a. Con ...
Other materials:
Assembling the front brake caliper
WARNING
Before installation, all internal brake components
should be cleaned and lubricated
with clean or new brake fluid.
Never use solvents on internal brake components
as they will cause the brake caliper
dust seals and piston seals to swell and
distort.
...
Installing the exhaust assembly
1. Install:
Exhaust assembly "1"
Exhaust pipe nuts "2"
Exhaust assembly bolts "3" "4"
NOTE:
Do not fully tighten the nuts and bolts.
2. Tighten:
Exhaust pipe nuts "2"
Exhaust assembly bolt "4"
Exhaust assembly bolt "3"
...
Checking the front fork
1. Stand the vehicle on a level surface.
WARNINGSecurely support the vehicle so that there
is
no danger of it falling over.
2. Check:
Inner tube
Damage/scratches Replace.
Oil seal
Oil leakage Replace.
3. Hold the vehicle upright and apply the front
brake.
4. Che ...