These rugged wheels are designed to press-fit securely onto the 3mm D output shafts of our micro metal gearmotors and 15.5D metal gearmotors. These gearmotors should be mounted onto the side of the hub with the protruding teeth, as shown on the right. The output shaft will slide into the socket easily at first but will achieve a snug fit when pressed through to the other edge of the hub.
The output shafts on our selection of Solarbotics metal gear motors will also fit these wheels, but because they are shorter they will have to be mounted onto the other side of the wheel where the fit is tighter (which means the Solarbotics metal gearmotors will not work with the quadrature encoder associated with this wheel). These wheels will also work in this orientation on our mini plastic gearmotors with 3mm D-shaft outputs.