Rear brake

[Hans1940]

I have a new Radrunner 2 and I like the e-bike but the rear brake doesn't seem to be working right. The front brakes work well  but when I apply the rear brake it doesn't really slow the bike down no matter how hard I pull on the lever. I cleaned the disk with alcohol but that didn't make any difference. Thanks for any help.

[Si1Dia]

try cleaning the rotor, sanding the rotor and brake pads, bedding, and trying it again. this video is great to govern the process of doing this.:

https://youtu.be/qsZPUyFZaxQ

[Hans1940]

Did what you suggested and also watched the video, still not as good as the front brake but the rear is a lot better. Thank you.

[Rover80]

Make sure the caliper is centered to the rotor. If it is slightly off center, you won't get proper/complete contact between the pads and the rotor. Loosen the caliper mounting bolts that hold the caliper to the frame, so that there is a very slight bit of physical movement of the caliper. Then compress and hold the brake lever while re-tightening the caliper support bolts to the proper Newton Meter specs.Your caliper will now be centered to the rotor.

[Hugh]

Try replacing the brake cable.  It may be defective causing spongy lever feel.