Our previous trailer was a Coleman Pop up. I custom built a frame mounted hitch so we could use our bike rack on the rear or the trailer, and then transfer the bike rack back to the van once we were at the campsite. It was the smaller class II square type that I though it was tough enough because the bikes and rack weighed less than 75LBs.
Our first outting was a 2 day drive to Murtle Beach. All went well on the way down but on the way back going through Pittsburgh one of the components broke. (see diagram). We dragged two bikes and the rack down the highway for ???? miles.
Here are the things I learned from this experiance.
A. A 2 inch type III style of hitch is a must.
B. A safety chain is required ( which I did have ) on any device that is being carried.
C. Uhaul sold me a 2,000 LB lift bar hitch. I thought they were all 3,500 LB rated.
D. There is a large bounce factor on the back bumper of a trailer.
E. If you are going to use a bike rack I would suggest adding a support line of some kind to stop any up and down type of bouncing that will occurr.
Although it seems like a convienient spot to put bikes I would use it as a last resort. Our bikes go in the back of the van.
Airstreams..... The best towing trailers on the planet!