Could you explain what ´Kunstradfahren´ or ´Saalsport´ is please, it is new to me.
I´m no expert, but it´s best described as cycling crossed with figure skating. It was and still is fairly popular in Germany, hence the German terms (Kunstradfahren translates loosely as figure cycling (literally art cycling) and Saalsport as Hall Sport (it seems to be practised indoors mostly). I only know a bit because a friend, who is into trick biking, picked up a kunstrad frame at a a bike jumble in Belgium and we tried to figure it out. The bikes are quite specialised for their task, you can see an example here http://www.embacher-collection.at/radseiten/3-1-AUGUSTRABENEICK-Saalsportrad-en.html
Here´s a video
Unfortunately the frame my friend picked had well camouflaged and dangerous damage in the fork, so haven´t seen it in action.