Due to manufactures making various claims on miles per charge i just thought id share my experience on my bike.I bought my Haibike hardseven last November but always charged my battery after every trip usual y around 20miles.Last time let the battery run down to a single flashing bar so basically flat.It worked out that i got around 45 _50 miles using the standard setting on the Yamaha 400w system.This was doing light track and rd work.I hope this helps any body who might be looking for a bike choice.