Loss of power

[mark156531]

I just finished building a new ebike using the parts from my previous build. On my previous build my e bike would get up to a speed of about 30 mph and use as much as 1200 watts when accelerating. This new build only gets up to about 17 mph and uses about 400 watts when accelerating. The battery sat all winter in my garage but it shows all bars on the sw9000 display and 3 of 4 bars on the battery. I do not have the pedal sensor connected. Does anyone have an idea of what might be wrong.

 

[Annieolnie]

Try checking the battery with a multimeter to see what it's actual charge is. You might have one dead cell.

 

[mark156531]

I haven't charged the battery since September and the multimeter shows the voltage as being 51.9. is there another test I can perform on the battery?

 

[Annieolnie]

A 48 volt battery should charge to 54.6. Have you tried charging it fully, so it can go through a balancing, if so then you very well may have a bad cell. I don't know if you are in the U.S. or not but you may have to send it out for repair.