Spooky Electrics - 85 K100 Rs

[Carguz]

After jump-starting my bike the other day. The bike has stopped running at lights. It has been increasing in frequency.

Latest symptons: Stops dead at the street light, the dash panel and panel lights become very dim and the starter wont turn. I wait a few moments then the dash panel lights become bright again and the bike starts. Symptons now include a tach reading of about 5000 RPM while the lights are dimmed out and unable to start.

There must be an intermittent short somewhere. Question is where do I start looking, cleaning, spraying, etc.?

Any help as always, VERY appreciated.

[aaaaaa]

I owned an '85 K100RS. It was blue. Very first year of the K bike. Can tell them apart because the passenger grab rail is integral with the seat. The instrument modules were prone to failure on those. Moisture has probably gotten into it. Other than that they were rock solid machines.
robert

[hhshort]

1. Check the battery connections.
2. Check the Battery ground at the tranny.
3. question the quality on the battery ground cable.
4. Wiggle the Ignition key when the malfunction occures. If that causes any change in the malfuction the switch needs cleaning.
5. Cleaning the switch is discused in the IBMWR web site.

If none of this helps there will be others that will chime in. Harold

[Bobmws]

In addition to checking the condition of the battery cables (they can corrode internally), the wire harness grounds on the backbone of the frame. Remove the tank and you will see about a dozen wires connecting to ground at that point. remove the bolt and clean all the terminals.
Another possibility is that the starter needs to be dissambled and cleaned, as that is a major ground circuit. There are good instructions in the tech pages at IBMWR.org.

[Kayseventyfive]

The bike has stopped running at lights.

Does it stop running at stop signs, too? Not joking, here, but since lights have longer sit times than stop signs, it could mean something.

[deilenberger]

When it does this - try wiggling the key. Not an uncommon problem - dirty ignition switch. They do that..