[axx]

It would be quite interesting to see how these “tire contact” motors will perform once it starts raining or your tires get really dirty.

I think there is a reason, why crank or hub located motors are the norm now.

[swader999]

You are right about this.

This article does a much better job of exploring friction drives on bikes. https://www.electricbike.com/friction-drive/

The Kepler drive is the best design I've seen and the build/design thread on that shows you all the issues and challenges. It's quite impressive. https://endless-sphere.com/forums/viewtopic.php?f=28&t=25645