Makes me wonder about the wheel’s rotational inertia, too. In theory, a hubless wheel could be lower mass overall without the need for a center axle/hub and spokes connecting the outside to the center. But that’s all weight saved in the center of the wheel with lower effect on overall rotational inertia. Visually, the picture that makes the thumbnail in this post shows that the brake disc has to be further from the center of the wheel, which I imagine adds a lot more weight (more material necessary for the overall brake disc being a larger circle) and a lot more rotational inertia (further from the center).

Maybe the whole design itself can save weight in certain places that make up for the weight added in other places. But I just have a ton of questions, and am overall pretty skeptical of the long term potential of this design.

Looks cool, though, I guess.