Trailer hitch between a bike and trailer? I want to make a bike cargo trailer.  It seems to me that making the hitch will be one of the most difficult parts so I opened a separate question for this.  

How would you attach the trailer to the bike?  Would you attach it at the seatpost (high) or near the wheel axle (low).  How would you allow the trailer to pivot both up and down and side to side?  

See also: How to make a cargo trailer.
I would also go the commercial route, buying the hitch and building only the trailer itself. The handling (during cycling) of an axle attached trailer is much better than if you attach it on the seat post. Handling is best if the hitch parts can move as little as possible relative to each other. The Chariot hitch is pretty good, especially considering the fact that only one axle/quick release module fits a wide range of dropout designs.

Still, everything can be improved: The German company Weber makes a hitch system with the following highlights:


extremely rigid connection
very simple and fast to use
fits most frames perfectly by providing different frame/quick release attachment parts, even for geared hubs etc.
fits basically any drawbar, by providing inserts for any commonly used tubing size
can easily be locked (although the lock won't scare a good lock picker)
an integrated bike stand is available
quality and safety are top notch, and the parts last a long time




Weber hitches are easy to get hold of in Germany. It should be possible to get them exported to almost everywhere. Unfortunately the information is in German only, and the system is rather complex with all the different frame and drawbar fittings.