I live in the USA and if I want to get rid of my car I would need to be able to cover 70 miles round trip with moderate exercise in a reasonable amount of time. I think if I could cruise at 35MPH (56 KMH) that would be enough to make the switch.
It may be stupid, but I'd like to try to avoid an electric motorcycle - those need insurance, registration fees, real parking spaces, and a special license. Also, I enjoy getting some activity while riding. FWIW I'm not worried about legality, but I do plan to stay off bike paths/sidewalks to avoid endangering pedestrians and other cyclists.
My idea so far is to start with a gravel bike frame for aerodynamics, efficiency, and sturdiness in case of a pothole or rogue curb. From there I'm thinking about a 1500w hub motor, dual batteries, higher gears, bigger brakes, and permanent lights for visibility. Also a good helmet of course, crashing at that speed can be pretty bad.
Has anyone done something like this and had it go well/poorly? Anything I'm clearly missing in my plan? Also feel free to tell me if I'm an idiot, but I already know that bit.
You don't need a bike, you need a great public transport system. Great means service every 5 minutes all day, every day. System means the entire city is covered with great transfers to express routes that move fast to close to where you want to be. It can be done, and would be cheaper than a car for everyone in your city in the long run, but it will also be expensive to get there. Good luck.
You're not wrong but public transit here sucks. Every weekend I go to a friend's house - by car it is 1 hour every time. By train it is somewhere between 2.5 and 3 hours depending on delays. Public transport (even when poorly implemented) offers a great way to get in/out of medium to large cities, but isn't really ideal for trips from one rural area outside the city to another. What would be much more convenient would be if I could bring an ebike on the train with me. Most of the distance on this trip is covered by a 1h train ride, and it's just the busses on either end which are slow and unreliable. Unfortunately they don't allow electric bikes at all, and normal bikes are only allowed during certain hours.