Tamiya 70203 Low-Current Motor Gearbox (3-Speed)

The Tamiya 70203 Low-Current Motor Gearbox (3-Speed) is a compact and energy-efficient gearbox kit designed for low-power applications. It includes a brushed DC motor and the complete gear set to configure one of three gear ratios: 12.7:1, 38.2:1, or 114.7:1. The motor runs on 0.5 to 3 volts and draws only 20 mA when free-running at 3 V, with a stall current of 670 mA, making it ideal for battery-powered builds and small robots. The gearbox uses a 3 mm hexagonal output shaft, 100 mm long, which fits with many Tamiya wheels and LEGO wheel adapters. It can be mounted in two orientations and features a transparent casing to view the internal gear movement. The kit comes with illustrated instructions in Japanese and English, and only basic tools are needed for assembly.

For those building compact robots or experimenting with gear ratios, this kit offers a reliable, versatile, and easy-to-use platform. The ability to swap between speed-focused or torque-heavy setups makes it well-suited for prototyping, STEM education, and hobby projects. The low-current motor pairs well with compact motor drivers like the DRV8835 or DRV8833, keeping your electronics simple and efficient.