We use a couple of different bike fork mounts to haul our various bikes in the back of the van. Different bikes use different sizes of mounts. Rather than having to swap out several different mounts depending on what we are hauling, I created a single holder that holds all our mounts. Now I can easily add or remove all the mounts with ease.
I spaced the Rocky Mount thru-axle mounts slightly offset so our mountain bikes can fit close together. Quick Release mounts for our old road bikes (no disk brakes/thru-axles) are spaced so the road bike drop handlebars will fit. It is currently configured to hold 2 mountain bikes and 1 road bike or 2 road bikes. The width of the holder is just about as wide as it can be without blocking access to the gear slide release knob.
It attaches with just two t-bolts into the gear slide. These bolts are tightened down using knobs so you can easily install or remove it without any tools. The two t-bolts fit in slots that allow you to easily move all the mounts fore and aft. This makes it easy to slide your bikes as close to the back door with out the door hitting them so you can maximize space in the front of the van.
This was just a prototype I made with some scrap 3/4″ plywood. So it isn’t very pretty. I cut it out with my CNC router. I may make something nicer. But so far this has functioned just fine. If I make a newer version, I will likely make it a toolbox instead of just a board and store my bike tools in it instead of carrying a separate large toolbox that I currently use.