I regularly do 50-55 miles at 20mph and 40-45 miles at ~25mph, using a 48v 30ah battery with a 48v 25a controller and a GM 48v 1000w motor. (HBS-48v1000w). That's about 25wh/mile.
When I get the chance (re:money), I'm going to change over my controller to a 60v (25a) one and run my 12v 40AH TS battery pack in series with my 48v 30ah one. I should be able to get 30mph at about the same mileage (roughly 50 miles). Or approx 36wh/mile.
So you have at least ONE member here who will be doing what you're going to accomplish too.
