[0]: https://www.digitaltrends.com/outdoors/asus-made-an-e-bike-c...

recent news: https://www.bbc.com/news/articles/c89nyk4pz74o

- they have functional pedals (otherwise it's a motorcycle of some kind)

- they require pedal assist at all times and have some kind of power or speed limitation (anyone can use this, or at least it is least restricted)

- they have pedal assist available and have a different, higher power or speed limitation (usually reserved for 16+ or something similar)

- they have a power or speed limitation that makes them suitable for adults only but doesn't require a driver's license or inspection

There are efforts to regularize these, and also efforts to make things more chaotic. For example, New Jersey decided that all ebikes require a new ebike license and vehicle registration. Across the river in New York, no ebikes require a license or registration, and may be operated on any street which has a 30mph speed limit or less... but cities are allowed to make their own rules.

California's laws are mostly regarded by bicyclists as being sensible, at least in every discussion I've seen that didn't feature a twelve year old trying to convince his parents to buy him a 70mph electric motorcycle. See https://thecyclistchoice.com/resources/california-ebike-laws...

It has a removable battery so it seems the mechanism is designed to be left on the bike.