First, some background.

Part 1:
I had installed and since removed a Throttlemeister throttle lock on my Swing, and earlier this year I had inadvertently hit the safety kill switch while activating the throttle lock during highway driving. If you have never hit the kill switch while driving, give it a brief try. You should know/feel/hear how the engine reacts when killing the fuel/ignition while driving. You won't damage anything. That knowledge of the sound of complete engine electrical failure can come in handy later.

Part 2:
Several months ago, I was driving sedately along a smooth country road at 30 mph 2up, when out of nowhere, my engine briefly lost all power, just like hitting the kill switch. I held the throttle and power came back by itself in about 0.5 second. I was concerned but chalked it up to alien intervention, as I had no idea what caused it and it never returned.

Part 3:
Until yesterday. Taking a long road adventure with some riding buddies, we left a lunch stop out in the boonies, doing highway speeds, when all of a sudden my engine seems to start surging. It briefly lost power, regained it, lost it again, for about 5 minutes. It was like that safety switch was being rapidly flicked on and off. After about 5 minutes the engine behaved normally. I was accelerating pretty hard afterwards to perhaps clear any possible deposits out of the injectors, blow any carbon out of the O2 sensor, check the ignition and plugs for breakdown, but it accelerated just fine with no missing. It seemed to surge only at steady throttle openings under light to medium load. At the next stop I told my buddies. 3 of the 4 of us are tech types, one being a professional tech with a huge amount of drivability troubleshooting with Ford. We all thought it might be an O2 sensor or electrical issue. I checked the battery terminals for tightness, but those were good. The reason we chose the O2 sensor is that was the only thing I had done to the Swing recently. I had removed it when I changed mufflers. On reconnecting it I knew it was in firmly from the sound of the click.

I knew it wasn't an ignition/spark plug issue, as the bike accelerated hard and didn't miss or surge under heavy load. I ruled out the O2 sensor as the engine was not running rich. My fuel consumption was normal, there was no evidence of carbon in the muffler, and the engine would go into closed loop operation.

Part 4:
This morning I woke up, thought about how I would tackle this problem, and it hit me. My engine was behaving as if someone was flicking the kill switch very rapidly but totally randomly. What else on the bike could do that? Honda's switch gear is of very high quality and reliable. I doubted it would be a defective safety kill switch and I had never heard of ignition key wiring issues.
Did I hear someone say "side stand safety switch"?`
I had bypassed my side stand safety switch last year with a spade lug. It was a press fit held in place with electrical tape. That spade lug was getting loose inside the connector, causing a very brief and intermittent loss of complete electrical power to the engine.
I pulled the loose spade lug, reconnected the the safety switch, and I am now sure the problem has been solved. Since it was so intermittent I'll need some time to verify, but as I said I am 100% confident.

Thanks for the heads-up bigbird. I may go back and reconnect my sidestand kill switch even though it hasn't given me any trouble (yet).

Gar

I have the side stand safety switch modification. Not going to remove it until I get an inkling there may be a problem.

Now Bigbird has identified a potential problem I will monitor. At the moment I have had no symptoms. The spade connector I have fitted was a very tight fit so am quite confident! (As I type.)

I'm quite confident I could rectify the problem and continue using the bypass. However, after riding all day yesterday with 3 other guys in the same age category, it seemed that every time we stopped one guy or another would forget to do something in regards to his apparel or bike when getting back underway. None of them had side stand bypasses. Sooner or later I know I will drive away with the side stand down. It's just a matter of time. Between the helmet down and locked, gloves on, parking brake off, and side stand up, that's a long checklist for each departure. By eliminating the side stand up from the checklist, at least I can drive away without doing major damage to me or the bike by the time I realize I've missed something.
I'm not preaching at all, but just saying I don't want to be a bigger risk taker than I already am.

Agree with you, I am fortunate being an ex aviator, checks prior to driving/riding away are currently habitual. I wasn't aware I was actually doing them until whilst car sharing a work colleague pointed out what I did.

When I alight or park the car I return all switches to their 'null' position or off.

Always better to err on the side of safety.

I don't think much about it because I nearly always use the center stand. Seems the bike wants to tip over too easily on the side stand. My checklist includes making sure my backpack is properly secured because I almost drove off one time with it just sitting on the passenger seat... OOPS!

thought about removing SS safety switch long ago,,,but decided against it...thinking about it again! (I like the idea of having it only start if the parking brake is on!)
but think it would only be a good idea if I remove the side stand all together!