I used to be into pre-digital home stereos pretty deep, & have learned a few things about sound & vibration running sound for productions at the Omaha Community Playhouse, & learned a few things trying to keep teachers with neighboring rooms from... becoming upset... when I was doing lessons dealing w/ sound using a keyboard plugged into a reciever & some good sized speakers in my room.
But I will yield to any acoustic engineer members who wish to ammend what I'll offer.
Please be patient while I try to get around to the actual motorcycle concerns you ask of.
For keeping teachers friendly (or apartment neighbors) one must reduce the low frequencies that travel through walls. (This is what late-night drive-by punks with bozo-bass-mobiles need to become civilized to.)
Low frequences tend to shake right through standard home/work barriers. Hi freq's tend to bounce off.
Vibrations can mechanically travel directly through the speaker housing into the shelf & into the wall.
Point the speaker an inch+ away from the wall(s) you wish to "respect" and set in on top of an inch thick layer of sheet styrofoam (packing shaped bits work), which goes on top of a layer of 1/2" plywood, which goes on top of a different type of rubbery foam stuff.
The various densities end up working to block mechanical transmission of various frequencies.
Acoustically, a "dead room" is one that has lots of irregular and or "soft" surfaces that absorb high freqs. This can be good or bad. A movie theater ADDS soft stuff to the walls and back of the room to avoid phone booth-like (um, remember those?) barrel-echo effects, which are unpleasant. The soft stuff is like the panels used in hung ceilings (strand board?) along with carpetting on the aisles, cushioned seats, heavy curtains... and lots of popcorn-filled viewers!
These examples, I hope, are useful in brainstorming a cushion-mount design for an on-cycle camera system. Low frequency thumps and bumps are akin to dropping a camera: the suddenly applied G-forces are not good for the camera mechanicals. Meanwhile, any high frequency vibrations can do bad things to electronic components, and for loosening screws.
So...
If the camera were to be mounted behind/within one side of the fairing and have a super-clear plexiglas (or?) window to "see" through, then it could be weather protected, at least somewhat theft protected (out of sight ).
Vibrations...
The suspension oughta protect the camera from major thumps. If the camera is held within a double density foam design that ought reduce the problem high frequencies. If the camera happens to have built in shake-control all the better. Shoot, it wouldn't be too hard to add some extra-soft-rubber mounts to ALL the attachment points of the fairing frame. That could even add a little longevity to the headlight bulb... though they're pretty tough.
One trick would be to make the camera on-off controls & memory card slot(s) available to the rider.
Which depends on which camera you select.
Well, it's a start. Bart