The video shows a close-up of a bicycle wheel with a black rim and spokes. A person's hand is seen removing the rear wheel from the frame of the bicycle. The hand then unscrews the silver and black hub of the wheel, revealing the black gears inside. The person then removes the gears from the hub and cleans them with a white brush. After cleaning, the gears are put back into the hub, and the wheel is reattached to the frame.