I've been having problems burning bulbs out, so I took a look at my regulator (and quite a few old posts) to see what was up.
First: it appears I have an aftermarket rec/reg, one of these (Link!) from AF1. It also appears that the PO got rid of all connectors, simply splicing all wires together directly. Finally, it appears the wiring mod had not been done - no extra wires to the main fusebox, no extra 'yellow' wires, etc.
Now, with the bike off my battery measures 12.99V. So far, so good.
I turned the bike on and let it idle, the voltage at the battery was initially ~13.5V, and began slowly climbing, with intermittent spikes in the 17V (!!!) range. After a few of these spikes, I turned the bike off, for fear of frying things that are much more expensive than bulbs. By that time, the voltage (excluding the spikes) had risen to ~14.4, and was continuing to rise. I did not run it at 4K rpm, for fear of angering the electric gods.
I know there are two possible culprits, based on prior forum posts: either (a) the rec/reg has gone belly up, or (b) there is either a bad connection somewhere, likely a ground.
I have a decent knowledge of electrics and the like, but am by no means an expert in bike charging systems -> which of the above two options is more likely the failure point with my above symptoms? I'd like to know where to focus my attention, hopefully in short order because I have a long ride planned for next weekend, and would need to order a rec/reg in short order if it has down the tubes.