Universal gear indicator for motorcycles

This is a new design for a universal gear indicator that can be installed on any motorcycle as an aftermarket accessory. Its main advantage is that its operation depends entirely on the movement of the gear lever, rather than being connected to speedometer and tachometer sensors (found in expensive commercial equipment), which are rarely found in older motorcycles. It consists of a main circuit including a 7-segment LED indicator, two Hall sensors attached to the motorcycle frame, and a small magnet placed on the gear lever.

The main circuit is based on the AVR ATTINY25/45/85 microcontroller, reads the signals of the two Hall sensors and the neutral switch, and outputs the current gear number to the 7-segment LED indicator through the 4026 counter/decoder. At maximum output power, IC1 generates a lot of heat, so we mounted it directly on the ground plane for maximum heat radiation.