1. Gather the tools you will need and familiarize yourself with this controller diagram:
2. Unplug the battery (if charging) and ensure it is in the OFF position.
3. The controller for the RadMini is located behind a metal plate held by 4 screws near the bottom of the bike. Remove this with a Phillips head screwdriver to access the controller.
4. Unplug the 3 connections to the left, and remove the rubber grommet in the right hand corner where the motor connector goes through using a flathead screwdriver.
5. Carefully cut the zip ties for the motor connector located about 6 inches away from the motor on the other side of the bike, and unplug the motor connector.
6. Pull the rubber grommet over the motor connector, and pull the motor connector through the controller box to remove the old one from the bike. The grommet will be pretty tight between the cable housing and the grommet, so if necessary, loosen the cable located on the brake caliper itself with a 5 mm Allen key. Once loose, the cable housing can be slid into the controller housing and you can slip the grommet over the bare metal cable and the motor connector.
7. Now everything is unplugged! Pull the old controller out, and plug in the new controller, using the reverse of the steps above.