It's an older thread, sir, but it checks out.
I'm now plagued with pretty much this exact problem. It sucks.
I had the Signal fuse blow for seemingly no reason, a few months ago. I only noticed when leaving for work one morning. When I made the first stop at the end of my street, I found that the turn signal was not working. Nor was anything else dependent on that "Signals" 15A fuse - dash lights, dials, etc. Took the car to work, later found that Signals fuse had blown, replaced it, no problems for months.
Then this morning, Signals fuse blew twice.
As before, not sure when it blew. Noticed once I reached that stop sign, on my way to work. Turned around, parked in the garage, found my spare mini-fuses, replaced the problem one.
Exact same scene played out again. Gave up on riding to work today. Replaced the fuse yet again.
I tried making the fuse blow, in my garage once I had my gear stowed. Figured maybe I could hear something pop or crackle or see smoke. No dice. Nothing unusual at key to "on." Engine started & ran. Using turn signals didn't make the fuse pop. Need to do more testing/inspection.
I've made some changes to the electricals recently, but it was all with brand new Eastern Beaver gear. A short being introduced by any of that seems unlikely. Also, I've been riding for a week with the EB stuff installed & not had any problems.
I might try riding the other direction, when leaving my driveway. Possibly the fault only happens with left or right turns. That could give a clue where to look for the (presumed) short.
Why is this Signals circuit a common problem with older Vees? Must be some specific part of the wiring harness, or switch, that goes bad over time.
2007 Vee with too many farkles and 50k+ (s)miles