I was thinking that the frequency would be lower for a 4 stroke vs a two stroke, but the piston (probably the greatest source of vibration) would still be stroking the same number of times. There is some additional impulse shock from the fuel detonation which occurs 1/2 as often in a 4-stroke. The frequency of vibration is probably lower in a 4 vs a 2 stroke and therefore easier to dampen?

I agree that dampening the camera mount is the best way to go.