When the bike is hanging on the wall there is large space between the wheels and wall. To save some space under the bike, I have 2 hooks to pull the wheels closer to the wall. That “thing in the middle” is there to prevent turning of the front wheel.
You can upgrade it, Fusion 360 model attached.
Printed from PETG (25% infill, 3 perimeters) seems to be strong enough .
The author marked this model as their own original creation.