Before running gas engines, I ran 72 vdc thru a front electric hub. Low end was good, but top speed was only 27 mph. Sadly, this was NOT fast enough to ride in traffic, and charging 80 lbs of batteries daily was labor-intense. So was removing & reinstalling the batteries AND carrying the bike and batteries up two flights of stairs.
My gas-powered commuter speeds to 40 mph+
fills up every eight days and keeps up with traffic. Upon arriving home, I push the bike up two flights of stairs. It is safe from the weather and thieves.
It is EXACTLY what I was looking for.