Is there anything bolt on? Because its just a bike (75lbs if I get an Aventon Aventure) are there other solutions for bike only?

There is a factory trailer hitch for these rigs. It is a small plate style receiver with its own stinger. I have taken a 2" adapter and bolted it to one of mine to use for light duty towing so I am sure it would hold a mt.. bike rack. They also make a 1.5" receiver that is a little harder to find and even the rare 2" receiver. 

Thanks. I did find an 1 1/2" hitch off Amazon. Couldn't find a 2"

Thanks. Have successful installation