Need a commuting solution
I have been reading a little bit here and I have an idea of what I want to do. Currently, I commute 6.5 miles one way via bicycle, and it is going to stay that way for some time. What I would like to have is an electric bike that would be either full electric or pedal assist (I'd probably get lazy and not really pedal all that much anyway).
I am looking for speeds in the 20-25 mph range. I am not a speed demon who is going to buzz small children, I just want to get to where I am going in a timely fashion. This bicycle is meant to be a car-killer. I do not own a car and have no intention of owning one anything soon if I can help it. Currently, I try to average 13 mph or so, but if I have favorable wind I'll try to pedal 20mph. (I once had really favorable wind and did it in 21 minutes...average speed 17.42 mph)
Option A would be your usual Hub-motor job, I would buy a kit online and refit my bike (for future reference, the bike who is going to be involved in the project is named Betsy...) and have it be a conventional setup.
Option B would be to take a motor with a sprocket on its shaft and chain it directly to the forward set of gears (I have a 3x7 setup) via the smallest gear. I will probably take a hacksaw to the cranks and lop them off to avoid the manic-ankle-breaking-spinning-pedals problem.
I would prefer Option B. It would make sense to me that this arrangement would enable higher speeds through the use of the bicycle gearing. As I said before, the speed factor is to get there, not because I have to have a gale whipping through my hair.
That said, what motor/battery setup would the forum recommend? What means of mounting the motor would you recommend?
Please, constructive criticism is wanted. Thanks!