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Cleaning the Ignition Switch

Cleaning the K Bike Ignition Switch

By Bill Wagaman

The following is the procedure I used to clean the ignition switch on my 1988 K75C. I do not know if the ignition switches for the R series are the same but I would expect them to be similar.

Symptoms: Engine would all of a sudden die. Gauges looked like the ignition key was turned off. Wiggling the key in the on position would bring the bike to life. Sometimes get dim charging light at idle.

The switch:The ignition switch on the K bike is a switch unit with a 18″ long or so connector wire. The connector part is under the fuel tank. The procedure is to remove the switch from the switch pad, disconnect the connector under the tank, disassemble and clean the switch, reinstall.


  1. Disconnect negative lead to battery.
  2. Unbolt the switch pod which houses the ignition switch.
  3. Remove fuel tank, wiggle the wire from the ignition switch and follow the wire to the connector near the center frame. Disconnect the connector, cut the wire tie near the head tube and pull out the wire.
  4. Remove the circular switch bezel around the switch with a small screwdriver. You will see 2 rectangular openings at 3 and 9 o’clock next to the switch. Insert a screwdriver in each hole and release the switch. Push the switch backwards and out of the switch pod.
  5. You should now have the ignition switch complete with pigtail ready for surgery.
  6. Remove the rear plastic guard. This somewhat protects the rear of the switch, wiring end. I would highly recommend marking the length of the switch with a marker at this time to ease reconstruction.
  7. The switch is divided into 2 halves. The front half is the lock part, the rear half has the switching part. To remove the rear part of the switch from the front half is simple. There is a small recessed screw I believe at about 12 o’clock on the switch. Look for a bit of red paint on the outside of the switch. The paint is there to somewhat lock in the set screw. Use a small screwdriver and back out the set screw so that it almost falls out. The rear half of the switch should now come away from the front half. Put the front half of the switch to the side.
  8. If you look carefully at the back switch half you will see it is kind of a sandwich of gray, white, gray plastic. You want to remove the gray plastic section closest to the wiring. Insert a small screwdriver near two locking tabs on the gray section. This will release the gray plastic section, exposing the switch contacts.[See Ignition Switch Disassembly” for additional details – wd]
  9. In the switch section you will see several short springs, a triangular brass colored piece, a long 2 prong contact piece. Either make a drawing of how things fit together or remember how they go together. I do not think that you can put the switch back together wrong, it is easier to reassemble if you remember where everything goes.
  10. The first thing I checked were the center electrodes. They were coated with a loose black deposit in my switch. They look like a set of points. I polished up the these contacts with some metal polish. Mine was slightly pitted, but they polished up real bright and silvery. I then cleaned out the residual dirt in the rest of the switch. Then I polished all other contacts.
  11. I put some dielectric grease on all the contacts. I lined up all the parts in the order that I remembered and snapped the back gray half back onto the back half of the switch. I then inserted the front half of the switch, reset the set screw.
  12. I would recommend at this time reconnecting the ignition switch and the battery before reinstalling the switch into the switch pad. I connected the switch and battery and tried it out. Everything should turn on as before. If all is well, disconnect the battery and switch. Put a little dab of paint on the external set screw.You then basically reinstall the switch by reversing the first 4 steps.

I feel that cleaning up the switch and especially putting some dielectric grease on the contacts should get you an almost new switch.

Mr Bill

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