Interesting.... thanks for the research. I've thought about looking in to this too
I like to bike when my wife and I go to the beach, but always leave the ZHP convertible home because it doesn't have a tow hitch for my bike rack. But $500 to $600 seems too steep for me to have that convenience instead of just taking one of my SUV's
Did some research too though, and it appears the standard ball size in Europe is 50mm, or 1.9685". Seems like that's close enough to our 2" used here in the states, but I'd like to hear a trailer expert confirm that would be safe!