You realize a motorcycle is a street vehicle, same as a car? It has a lot of the same requirements as a car, tail lights, head lights, covered by the same legal requirements as cars? I can't speak for the ECU, but I suspect modern ones have it, same as cars.
This thread fell through the cracks. Moderators can't catch everything, but sooner or later we will see problem threads.
When it comes to street vehicles, motorcycles are in the same class as cars.
As stated, this thread was considered borderline. It is part of the reason it lasted so long. Major changes to wiring inside a vehicle is definitely covered by ToS though. We had an interesting offline discussion about it.
At the moment anything that is not distracting to the driver and plugs into a cigarette lighter might be allowed. We are currently covering it on a case by case basis.
I did not make the rules. I do enforce them, as do the other Moderators. I did not close this thread, but if I had got to it first I would have. You know the rules, or should by now. The OP was new, he didn't know. Now he does.
You didn't see the harness because the OP was good at what he did. The fact is (and you know this) he had to splice in somewhere. This makes it an electrical modification.
Why the heartburn? This isn't anything new. Did you think street legal motorcycles were exempt?