LEGO-powered motor reaches 4,000 RPM with minimalist parts

A YouTuber builds a fully working electric motor from LEGO bricks, magnets, a hand-wound copper coil, a sensor coil, a transistor, and a 9-volt battery. Without a microcontroller or complex electronics, a sensor coil detects rotor magnets and triggers timed power bursts to the driving coil, producing self-timed rotation. The project illustrates core electromagnetism and feedback control, with rotor configurations claimed to reach up to 4,000 rpm and varying speeds/torques that can drive a small LEGO car.