Tinsailor, did you ever figure out what the problem was? (Forgive me if I missed it in the thread)
Quick self-intro: I've been lurking around the forum since I bought a 2012 C14 about 2 and half years ago, 3K miles when I got it, 26K on it now. Running it with Steve's decel flash and a Delk 14" can. I've learned a lot from the forum and have been meaning to join, but this thread really got my attention because I've been having the same (or a similar) problem. So here I am!
Like Tinsailor described, bike loses power, you can especially feel it when climbing a hill or accelerating, but can feel it kind of hesitating even when just maintaining speed on level road. If I'm accelerating hard when it 'hits', the decel is really strong, almost freaked me out the first time. Could be dangerous as well, I pulled out into traffic once only to have it decel when I needed it to accel!
I'm suspecting some type of fuel issue because it has become consistent when I hit around 180 miles. I ride to work every day, so my weekly route is really consistent, with consistent riding style. Over the last 6 tanks of gas, the issue has shown up on every one, each time at around 180 miles into the tank. I've tried pulling over and turning the bike off for a few minutes, no change. Tried pulling over and half popping the gas cap open (thinking possible tank vacuum?), no change or even worse. Checked the ground (yes, pulled the battery re-cleaned and re-tightened all connections). I typically gas up around this mileage anyway, takes about 4.2 gallons each time, so I know there's gas in the tank when the problem happens. After filling up the problem goes away until I hit 180 miles again. Gas is non-ethanol 90 octane, I run a bottle of Techron thru it every 2500 miles or so.
Bike hasn't been wet for a long time so I'm thinking its NOT the flash-to-pass switch or some type of electrical switch problem. Like I said, its so consistent now that I can predict it hitting within a mile or so of 180 on the odometer.