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:
Adjusting the front wheel static balance
NOTE:
After replacing the tire, wheel or both, the front
wheel static balance should be adjusted.
Adjust the front wheel static balance with the
brake discs installed.
1. Remove:
Balancing weight(s)
2. Find:
Front wheel's heavy spot
NOTE:
Place the front wheel on a suitab ...
Checking the spark plug
1. Remove:
Right side cover
Refer to "GENERAL CHASSIS" on page 4-1.
2. Disconnect:
Spark plug cap
3. Remove:
Spark plug
CAUTION:Before removing the spark plug, blow away
any dirt accumulated in the spark plug well
with compressed air to prevent it from falling
...
Checking and lubricating the cables
The following procedure applies to all of the inner
and outer cables.
WARNINGDamaged outer cable may cause the cable to
corrode and interfere with its movement. Replace
damaged outer cable and inner cables
as soon as possible.
1. Check:
Outer cable
Damage Replace.
2 ...