Toy Haulin': Here are some more pics. I'll try to describe and you can try to follow along in the pics. Basically, they took a piece of 2 x 2 about 18" long for the receiver. On each side of this, they welded another piece of 2 x 2 that runs over to the I-beams of the trailer frame. They welded a plate under this junction to reinforce it (1st pic). They cut a slit in the transverse 2 x 2's it so that the flange of the I-beam slides into the 2 x 2's and the 2 x 2's are welded to both the flange and the web of the I-beams (2nd & 3rd pics). Across the end (towards front of trailer) of the 2 x 2 that makes the receiver, they welded a long 1 x 2 (4th pic). This 1 x 2 spans the 2 I-beams of the frame and is welded to the underside of the bottom flange of the I-beams (5th pic).
As I said before, two bikes, no problem. I wouldn't put any more on it, though.
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10