Clean cockpits became a design obsession once frames started hiding all their cables, and the under-stem junction box was the last visible piece of Di2 hardware that broke the look. The EW-RS910 solves that by moving Junction A inside your handlebar, where it sits at the bar end in place of a standard plug. The external face shows only a small charging port and button, while the E-Tube connections happen completely out of sight inside the bar.

Two E-Tube ports handle the connections: one side runs into the handlebar to meet wires coming from the left and right shifters, which merge through an EW-JC130 Y-connector hidden inside the bar. The other port exits toward the frame, running down to Junction B and the rest of the system. For handlebars with internal wire channels, the entire cockpit stays clean with no visible wires. Handlebars without internal routing can still use this junction, though the wires will be external between the shifters and the bar end.

The face of the junction includes a charging port for the SM-BCR2 charger, a button for system functions, and LED indicators. Press the button to check battery status: green for more than 50%, red for below 50%, flashing red when charge is running critically low. The same button enters adjustment mode for derailleur indexing and handles rear derailleur crash protection reset. With a BT-DN110 battery installed, pressing the button also initiates Bluetooth pairing for the E-Tube Project app on your phone.... Read More