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:
Removing the fuel tank
1. Extract the fuel in the fuel tank through the
fuel tank filler hole with a pump.
2. Remove:
Fuel hose connector cover "1"
3. Disconnect:
Fuel hose "2"
CAUTION:
Be sure to disconnect the fuel hose by
hand. Do not forcefully disconnect the
hose with tools.
A ...
Removing and installing the cowlings and panel
Removing and installing the cowlings and panel
Cowling A
Cowling B
Cowling C
Cowling D
Panel A
The cowlings and panel shown need to
be removed to perform some of the
maintenance jobs described in this
chapter. Refer to this section each time
a cowling or panel needs to be ...
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
To check the drive chain slack
Place the motorcycle on the sidestand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
Shift the transmission in ...