Briang 1234
Thought that was my bike cockpit

I have had a GoPro on the bike for a while now. But still playing. My 1st position was on the fairing above the left indicator. But as you say if you have longer extensions you induce more vibration. Plus it was pulling the faring so didn't want to damage that. Taken that off now. I have thought of the position you have. As you say no picture of the bike. Havent tried it yet.
Presently using the "RAM Mount 1" ball and Thread bolt I have the camera in the Rightside extra mirror slot and the Controller in the left.
I will send a picture when I get back home.
The video I get is obviously part of the screen and it has moved a little just got to make sure they are tight connections.
I also run it with the Backpack so that has added a little more weight. But you can set up the video shot. One thing to be carefull about if you have it on the bars when you lock the steering and the screen comes down make sure it doesn't contact the screen.
So far had some reasonable video for me personnaly showing the bike and scenery so you get a perspective of road position for training and you remember where you went wrong on playback.
I also thought about fixing it under the headlight. You would just have to remember to alter the video on the camera as it would be upside down.
As I said still learning and playing myself. But it is usefull in case of any incidents.
seadog