A Garmin quarter turn mount with a GoPro connector. The Garmin adapter part could be used with any GoPro mount, the included lower part is for the Brompton handlebar bolt. Most mounts do not work as nice on the Brompton M-type handle bars (not enough space) and/or interfere with folding.
The aluminum GoPro mount (on some of the pictures) is from 1223. I was bored of waiting for it and created my own.
Update! I added an adapter that uses inserts.
Handlebar bolt mount:
- M10 rubber o-ring for the handlebar bolt
- M5x20 bolt and matching nut (GoPro bolt)
- 2 M3x6mm countersunk screws (5mm should work as well)
- 2 M3 nuts
Garmin mount is based on https://www.thingiverse.com/thing:2664759
GoPro connectors are from https://www.thingiverse.com/thing:62800
I suggest print it at an angle. This avoids most of the supports inside.