>Gopro uses a non-standard connector for the mic.
And that's why you don't buy a gopro. I'm so glad I didn't. I already broke-out all the connections for accesories on my drift.
Good thing is, you can get decent audio investing $0 on a mic.
The only thing I like about your gopro camera is that it has stereo mic input, that means 2 audio channels. Using 2 different mics you can process some sweet mixing on your videos.
Imagine one mic recording street audio and the other correctly placed on your helmet, you say something and mute the street audio, keep silent and enjoy the sounds of the street. It's even more useful if you interact with people, you'll be able to hear what other people say outside.