They've finally managed to reinvent the wheel. In a so-called 'hubless' wheel, the hub is actually a large thin ring that fits just inside the rim of a large bearing with the tyre on its outside. The inner ring itself attaches to the vehicle's frame. On a motorbike, the front wheel also has to handle the steering. With such an unconventional design, one of the challenges is getting power to the rear wheel. This can be done through a specially adapted chain or belt.
Answered by Gareth Mitchell