Y-Adaptor now available seen here
Also referred to as a shift sensor because this device will momentarily cut motor power while shifting. There are two types of sensor, one for regular cassette deraileur drive trains and one for internally geared hubs. Each type of gear sensor works a little differently. The GS-D is designed for deraileur type drive trains and the GS-I is designed for IGH drive trains. The gear sensor can be mounted in two places, either near the deraileur or near the shifter. Our BBSHD motors come equipped with the gear sensor cable so you can add it at the deraileur. If you do not have a motor with this extra yellow 3 pin connector, you can still install it near the shifter and plug it into one of your brake connectors. Soon we will have a Y adapter that will allow you to connect the shift sensor and have both brake switches connected at the same time.
Gear sensor manual click here