Tern GSD Hitch The Tern GSD does not come with a factory-installed trailer hitch. Given that the bike has 200kg capacity, it clearly would be useful for hauling trailer loads such as I've done with a regular bike. So I went about working to creat a solution. I started out with 3D cad working on a computer model for a prototype. The first version was not quite strong enough for the 100+ kilograms that were sometimes hauled with the bike and trailer. So more rienforcement was necessary. One of the main requirements of the design was that it accomodate two different trailer connections. One for a higher trailer with 20in wheels and one for a large capacity trailer with 16in wheels. I built a second version which attached to one of the frame bolts. This model required more precision in order to line up with the bolt and multiple frame tubes. You can get construction drawings (here). The final design had enough connection points that it could stand up to the forces of a fully loaded trailer and a bike that sometimes fell over. The hitch gets used every week and it's held up through rain, snow and various mishaps.