Yamaha YZF-R125 Service Manual: Checking the ignition coil

Yamaha YZF-R125 Service Manual / Electrical system / Electrical components / Checking the ignition coil

1. Check:

Primary coil resistance Out of specification Replace.

a. Disconnect the ignition coil connectors from the ignition coil terminals.

b. Connect the pocket tester ( × 1)
to the ignition coil as shown.

Positive tester probe
red/white "1"

Negative tester probe
orange "2"

Checking the ignition coil

c. Measure the primary coil resistance.

2. Check:

Secondary coil resistance Out of specification Replace.

a. Disconnect the spark plug cap from the ignition coil.

b. Connect the pocket tester ( ×
1k) to the ignition coil as shown.

Positive tester probe
orange "1"
Negative tester probe
spark plug lead "2"

Checking the ignition coil

c. Measure the secondary coil resistance.

Checking the spark plug cap

1. Check: Spark plug cap resistance Out of specification Replace. a. Remove the spark plug cap from the spark plug lead. b. Connect the pocket tester ( × 1k) to the spark plug cap as ...

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 ...

Other materials:

Checking the clutch housing
1. Check: Clutch housing dogs "1" Damage/pitting/wear Deburr the clutch housing dogs or replace the clutch housing. NOTE: Pitting on the clutch housing dogs will cause erratic clutch operation. 2. Check: Bearing Damage/wear Replace the bearing and clutch housin ...

Adjusting the engine idling speed
NOTE: Prior to adjusting the engine idling speed, the air filter element should be clean, and the engine should have adequate compression. 1. Start the engine and let it warm up for several minutes. 2. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 3. Lift the fuel tank. ...

Starting the engine
In order for the ignition circuit cut-off system to enable starting, one of the following conditions must be met: The transmission is in the neutral position. The transmission is in gear with the clutch lever pulled and the sidestand up. 1. Turn the key to "ON" and make sure ...