Bicycles are always a nuisance to manoeuvre within limited spaces. This applies especially to attempts to bring them aboard trains.
Today’s invention is to reuse the quick-release levers mechanism, which often holds the front wheel in place, to lock the transverse handlebar on top of the forks. Actually, only one of these would be required, the other side taking the form of a hinge.
When stowing the bike in a shed or on a train, the bar would be undone and then relocked in a vertical orientation.
This would enable bicycles to be stored conveniently and compactly and also allow rolling the bike eg through crowded streets without impaling pedestrians on the ‘horns’.