https://onlinebicyclemuseum.co.uk/ww1-german-bicycles/
https://news.ycombinator.com/item?id=25158215
Given that I haven't seen tweels for bicycles yet, I assume the feasibility studies did not go well.
It also looks like they also announced that bicycle tweels were 'coming soon' nearly two years ago: https://jalopnik.com/bridgestone-says-airless-tires-are-comi...