I think my point was that governments tax "because they can".
When (and if) ebikes become enough of a mass marketed product which people use regularly in large numbers it would be then that the government might take an interest in ebikes as a new revenue stream. Governments aren't dumb (well not completely anyway) and they are good at recognizing where the money is located. This is why the founding fathers had such a paranoia about government because they knew that if it can grow itself by preying on the people it will. (and always does)
Ebikes are at present in a state of "grace" in the eyes of the law in some areas and considered a problem in others. It kind of depends on where you live I think... cities seem to not want them, but suburbs see them as okay.
The "Outlaw" biker with his overpowered machine has the potential to attract attention to ebiking and motorized biking and that "could" force either a crackdown or a change in policy that would require registration.
All governments (federal, state and local) are hungry for money now... so the primary thing to fear is a money grab. If all of a sudden these motorized bikes require a $25 yearly registration fee that's going to alienate a lot of people and they will either quit or decide to go all the way to a motorcycle. Motorcycles are pretty much without rules except for the usual traffic laws, so if you really want unrestrained performance you can always just pay for it.
Money, power, politics.... it's always the same... we're human.
Bribery?
One could imagine some sort of government program where if you pay a small fee and get some sort of "moped license" that if you are then pulled over you could show that and get off no matter what modifications you've done on your machine. (maybe if you have a valid drivers license)
I've never been hassled... so it's not at present a big problem.
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Kerf, you are quoting one of my ancestors on my moms side of the family. (Sam Adams)
on the other hand if everyone followed the rules, there wouldn't be anyone riding, and our hobby would stay illegal indefinitely. us outlaws that ride anyway raise awareness of motor bicycling. more people that see us riding means more people that will be inspired to build their own, and once enough people start riding the government will have no choice but to update the law accordingly.