There is a local shop that builds bikes around the Bafang bbs02. They usually use the 36 volt motor with an option for the 48. The bbshd is also an option. They claim that the 36 volt motor will get the best range because it is less powerful. Is this true? What would you use if you don’t care about speed, 20 mph at most is plenty, but you care a lot about range? The bike would be used on road in an area where there are some mountain passes of 1000-1500 feet of elevation at no more than a 6% grade.