Yamaha YZF-R125 Service Manual: 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 sensor/stator assembly.
a. Connect the pocket tester ( × 100) to the
crankshaft position sensor coupler as shown.
- Positive tester probe
red "1" - Negative tester probe
white "2"
b. Measure the crankshaft position sensor resistance.
Checking the ignition spark gap
1. Check:
Ignition spark gap
Out of specification Perform the
ignition
system troubleshooting, starting with step 5.
Refer to "TROUBLESHOOTING" on page
8-3.
NOTE:
If the ignition spark gap ...
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 ...
Other materials:
Checking the steering head
1. Wash:
Bearings
Bearing races
2. Check:
Bearings
Bearing races
Damage/pitting →Replace.
3. Replace:
Bearings
Bearing races
a. Remove the bearing races from the steering
head pipe with a long rod "1" and hammer.
b. Remove the bearing race from the lower
bracket ...
Installing the front fork legs
The following procedure applies to both of the
front fork legs.
1. Install:
Front fork leg
Temporarily tighten the upper and lower
bracket pinch bolts.
NOTE:
Make sure the inner tube end position "a" is 24.5
mm (0.96 in) from the top of the upper bracket.
2. Tighten:
Lower br ...
Checking the cylinder head
1. Eliminate:
Combustion chamber carbon deposits
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damaging
or scratching:
Spark plug bore threads
Valve seats
2. Check:
Cylinder head
Damage/scratches Replace.
Cylinder head water jacket
Min ...