There are many many options. Here's a page that shows pictures of numerous methods to get you started - not all are sanctioned for 5ers and may also possibly depend on certain state laws (or your interpretation of those laws) as to triple-towing. Of course, GVWR and 5er axle loading (you may be adding a cantilever load thus multiplying the actual axle load) will be crucial calculations to consider.

You'll find many more manufacturers and ideas by Googling a variety of phrase like | motorcycle carrier | rv motorcycle | motorcycle trailer | etc. Products like these are often locally made and crafted requiring lots of internet searching to find what you are looking for. But the creativity abounds!