I build my own GoPro mount on my helmet
 

Because I did not want to glue something on my helmet and I could not find a GoPro mount that fitted my flip open helmet, I designed and made my own, together with my son.
I made a video while doing it and on new years day and yesterday I tested it.

In this video I did test the helmet mount with three different actioncams, two GoPro's and a cheap Chinese actioncam.
https://youtu.be/POEm-93_fSc