I ordered six wheel mounts for my trikes so that I can mount them on the roof of my car. They didn’t all come in in time so I had to create three of them.
I use schedule 40 PVC pipe bends. Cut them in half and added a hose clamp then attached to Yakama bars with some rubber.
I used some basic tools power drill, vibrating saw thing, some clamps, and a belt sander.
I used 400 lb test straps to attach the trikes to the wheel cups and mounting bar.
Here is a look at the factory manufactured wheel cups.
When you have a trip deadline and all of your mounting gear doesn’t arrive then you have to make due and get creative.