Chasing intermediate electrical things, can get a lot of hair pulled off your head looking for it.
Get your ohm meter out, remove side covers, start at the end, like a spark plug and work back wards to the battery. Each step, wiggle wires while taking a reading. If it fluctuates, find out why, if needed fixed, do so and then keep on moving to the battery.
By the way, suggestion, this is where I found my problem several moons ago, and also found a Gold Wing part to fix it. Under right side cover, is a good sized black boot protecting bunch of wiring. There is a connector on there with a fuse on one side. Inspect that connection good, as if you happen to wire something in and don't use a relay, it will get very hot and melt this connector.
This was mine at close to 200K, and now it has 242K and still running like a scalded dog.

Repair part;

If this is your problem and you order this part, the BIG Red wire has to be moved to the vacant slot to match the Valkyrie wiring. Be sure and use the larger Black Boot in the repair kit.
Here is a list of replacement parts for various problems, or maintenance.
http://www.jkozloski.com/generic_parts.htm