A while ago I modded my Carrera Vulcan by ditching the suntour controller for a derestricted generic one, this improved the bike quite a bit as I had a throttle and got full assistance when I wanted it. Since my controller is dual voltage and I was struggling with range in these colder months I ordered a 48v 13ah hailong battery and installed it. Hory shet! Can't vouch for the speedometer accuracy but I think it's within +/- 2mph. I'm getting around 24mph on flat ground and it will push to around 30mph on a gentle downhill. Hill climbing is off the charts. This motor was made for 48v in my opinion, it handles it well and only gets a little warm. The controller is rated 13 amps but the motor will pull up to 17 amps according to the display and so far the range seems promising. I'd estimate 25 miles using max assistance