Many people don’t use their bike’s gears to the fullest and therefore ride slower or more uncomfortably than they should, believes bike fan Jan Oelbrandt. Therefore, the tinkerer has decided to create an automatic solution for switching, which really takes all the work off your hands. You only have to steer and pedal it yourself.
Its Shift4Me system weighs very little and can be built and installed by the user with basic electronics skills and access to a 3D printer. It should work with both derailleur and hub gears, as long as the gear is operated with a shift cable. Even electric veins can be equipped with it. Even the highest improvements can be achieved by automatic switching, saving battery power and reducing wear and tear, explains Oelbrandt.
Shift4Me – the automatic bicycle shift
There’s a button on the handlebars to temporarily disable the automatic system.
The system consists of four components: a magnetic sensor that measures cadence, an Arduino nano (from €17.79) for control, a servo motor (PowerHD 1510MG) that pulls on the shift cable, and a battery pack. The sensor is installed near the pedals, while the Arduino, battery and servo are housed in a 3D-printed box that attaches to the frame. In the process, the shift cable must also be replaced and passed through the box. This allows the servo to move the shift cable instead of the levers on the handlebars. In addition, there is a button that is attached to the handlebars to temporarily disable the system and put the bike back into first gear.
Rebuild and adapt yourself
All parts, including 3D prints, cost about 150 euros, Oelbrandt says. With the proposed battery, eight hours of driving time would be possible. If the system runs out of juice, the wheel gets stuck in the last gear used. Preferences like the desired cadence, which the Shift4Me system should implement while riding, can be set in the Arduino program.
If you want to build the device, you have to register in the Shift4Me forum. The manual including 3D print templates, schematic and program from Oerlandt can be downloaded for free after registration. If there are any questions or problems with the replica, they can also be posted in the forum. If in doubt, Shift4Me can simply be removed again and the original shift cable used.