An Outside magazine article raised this question, specifically in reference to the HPC Revolution.
Here is the verdict, from Ty Brookhart and Wes Siler, the article's authors: "Because no one is going to buy an 82-pound bicycle, that essentially means HPC is selling a very light electric motorcycle that, thanks to pedals and post-sale programming, is legally considered a bicycle."
Got that? The pedals are there simply to fit the legal definition of a bicycle. That confirms what I suspected about many of the e-bikes I've seen lately: It's hard to imagine that their riders actually used the pedals. Or, if they did, it was difficult to conceive of using them for anything but starting the bike.
My purpose in raising that issue is not to rebuke riders who choose to motor rather than pedal. Rather, I mention it because of a concern I have: Those bikes are often ridden at motorcycle speeds, often in places where motorized vehicles don't belong.
I am not merely expressing anxiety over a "what if?" Instead, I am speaking from observation and experience--in particular, a close encounter I had with one of those "bikes" on the Queensborough Bridge bike lane last night. It was rolling faster than the cars on the main roadway, where traffic volume was considerably below that of the rush-hour peak. It was also faster than the train that rose from the tunnel and up the ramp--just a few yards to the side of the bike lane--to the Queensborough Plaza station.
The worst part was that I didn't hear the e-bike approaching me until the rider came within a few hairs from brushing against my elbow.
And, yes, that "bike" had pedals. More than likely, it also had the "programming" Brookhart and Siler mention--a speed limiter that caps the bike's velocity at 20MPH. That limiter, along with the pedals, allows such machines to be sold as "bicycles". As often as not, users remove that limiter. I'm sure that the guy who almost knocked me down removed his--or had it removed.
I am not the first to argue that such "bikes" shouldn't be ridden anywhere near where human-powered bikes are pedaled. If anything, those bikes are even more dangerous, to pedestrians as well as cyclists, because they are silent and less visible than cars or other motorized vehicles. But, as best as I can tell, as long as those "bikes" can be classified as bicycles, there isn't much anyone can do to restrict them.