I have a croozer kid trailer (actually a Mec.ca equivalent from the mid 2000's) and it has the same square spring loaded hitch that is in this question. I also am in the predicament of trying to acquire the appropriate bike-side hitch bracket for the hitch. But after reading comments about how the spring mechanism is not very pleasurable to use, I'm considering trying to swap out the hitch for a Burley or Chariot mechanism.
Note: I know this question is outdated, but I have come across several others posts of people looking to find a solution to this problem so I figured I'd post my research - it seems that as trailers change owners, the hitch brackets are often left behind!
I have dismantled the hitch from the Croozer/Mec trailer arm shown in this image:
The measurements are as follows:
- tube diameter: 23mm
- distance from end of the arm to pin hole (pin shown in the hole): 38mm
This post shows how an arm - very similar to this was replaced with a burley flex connector.
One concern is the video indicated the fellow had to actually cut back the arm in order to provide the flex connector enough length outside the tube.
The post provides excellent information about the measurements of the various parts (i've copied them here in mm):
- Round Tongue: 21.6mm
- Square Tongue: 23.3mm
More details about the Chariot parts can be found here: http://www.commutebybike.com/forums/two-wheel-bike-trailers/specification-on-the-chariot-hitch-cup-system/
One thing that isn't clear is the diameter of the hole in the lollipop or flex connector. In my case, the original hitch had a 6mm pin passing through the spring core connector. i found online that the lollipop pin is an M6 bolt, so it should work.
Due to the material of the burley, it's likely it can be made to fit, but since the chario lollipop is made of hard plastic, it maybe harder to modify.
I have a local store which has a Chariot Alternative Hitch (sorry not allowed to post more links) which I think I will give a try.