Two points with trailering. I have been hauling bikes since the early 70s and have towed 1000s of miles, all the way to Maine, Bonneville, and Northern California. In the old days it was either a board at the front or a simple hoop, the only common part was Ancra tie downs. In the last year I screwed up and ordered some Ancra soft ties from Amazon. When I was leaving California heading back to Arkansas I used the new soft ties for the first time on my beautiful 1973 Egli Honda. At our first stop in Arizona I opened the trailer only to find the bike on its side. The soft ties that showed up on my phone as Ancra were a Chi Com brand that would hold 5000 pounds, but not a 500# bike in my case. So I learned a $2000 lesson on making sure the package always says Ancra. Next, the fancy adjustable wheel chocks ALWAYS need to be adjusted to the front wheel size. Normally I have a bike with 17" front wheels, but an 18 or 19" front will allow the bike to tumble before you get the first tie down on there, so always adjust for a perfect fit. As to the drawing with just rear tie downs, I want belt and suspenders and will always use four of them.