At the heart of all e-bikes is a bicycle.
A bicycle with all the same components as any other: a normal bottom bracket, a normal pair of wheels, a normal headset, normal everything ...
This is good news, as it means they can be maintained, repaired or upgraded by any qualified cycle mechanic.
It also makes it much easier to choose your e-bike. Simply forget the motor for a minute and think about all the same things you'd consider when buying a normal bike: riding style, geometry, tyre tread, gears etc.
HOW TO CHOOSE YOUR E-BIKE
Ok, so there is one obvious difference...
Despite the similarities to normal bikes, with e-bikes there's one obvious difference and that is the electric motor. However, even this area is simpler than you might think. There are 2 main components to the 'e' element of e-bikes and they are the battery and the motor:
Battery - Simply dictates how far you can go. More expensive batteries will hold more charge and therefore carry you further.
Motor - Controls the torque. The more advanced the electric motor, the more torque it offers. The more torque you have, the more power you can get out of the bike.