My '86 K75 has had an increasingly 'on' charging system light. The light almost never comes on and stays on. Over 3500 RPM makes it go on and off, and hitting a large bump at that time tends to make the light come on. When above 3500 RPM and getting the light on/off, sometimes the motor cuts out, making a flat sound, then picks back up.
I've started it and checked the alternator output by putting a volt meter across the battery terminals and even when I put the emergency flashers on and make the brake light come on, voltage stays up around 13V. So I think the alternator is working fine.
I checked the ground with the bike off (battery ground to motor or other connected metal part) and ground (while the bike is sitting still) seems fine.
Are there usual suspects for connections to start with when trying to find this type of problem?
Any help is appreciated,