Chain hooks will fall out!
If your chains have open hooks then they won't stay in. Below, pasted from another post, is what I found with my little trailer when pulled by my Spyder:
The open hooks jumped out of the hitch within the first mile and you can't see or hear them dragging behind a Spyder - another kind motorist alerted me.
I cut the chains short and replaced the hooks with these but they would rattle loose even when I snugged them down with a wrench:
http://www.spyderlovers.com/forums/a...3&d=1423453195
I replaced them with these stainless steel clips (below) and they haven't jumped/rattled/fallen off yet. Remember that the Spyder's trailer hitch is attached to the rear wheel axle and has no suspension so that ball is jumping up and down with every move of the back wheel, amplified by the extension of the hitch.
http://www.spyderlovers.com/forums/a...1&d=1423452933
I used these on my Mini Trailer USA Nomad.
http://www.spyderlovers.com/forums/a...3&d=1423453195
They came loose the first time I used them (only hand tight). I then used a pair of pliers to tighten them and they never came loose again. If I remember right they cost around $5.00 for the pair at Lowe's.