During the course of your bike's ownership, it may become necessary to access the internal controller of the bike. This silver box holds some base-level programming for the bike, connects all the electronic parts together, and is vital for the bike's functionality. In this article, we will go over where to locate the controller, how to access it, and show the different wiring configurations. 

Step 1: Locating the controller

On both the Roadster and the Gravel Roadster, the controller is located at the bottom of the downtube under the trapdoor. 

Step 2: Accessing the controller

To gain access to the controller one has to remove the back trapdoor on the bottom of the bike. This is held in via two Torx 25 fasteners on the sides of the downtube. After they are removed it will lift off. It is best to have the bike upside down as the controller can fall out once the door is removed. If one does flip the bike over it is important to not rest the bike on the display.

Step 3: Working on the controller

Once the panel is removed, the controller will be directly behind it. The controller can slide out as there is nothing retaining it beyond the panel. While they may vary slightly the following tips are true for all controllers: 

  • Each connector is unique for each part. For example, a display unit cannot be plugged into where the motor cable would go.
  • When there are two of one component on the bike the plugs do not matter. For example: lights, a headlight, or taillight can be plugged into either of the controller ports, and it will perform the same function.
  • Pay attention to how the controller was originally sitting in the bike. The cables come out one end of the controller and for ease of reassembly, it is often best to put it back in the same configuration. 
  • When changing out a whole controller it is best to move the connections over one at a time until complete. 
  • Mark the new controller with tape or marker before starting. That way there are mix-ups during the switch. 

Controller connectors


To reassemble, repeat the steps in reverse order.