Last week I was driving a motorcycle. When I stopped at a traffic light I noticed the rear suspension dropped a little when I released the rear brake. Later I noticed my car did the same thing. When you suddenly stop, but not release the brake the suspension appears to be locked ("frozen") (See below image). When you do release the brake, the cars suspension appears to drop down to its resting position.
But why is this? As far as I know parts of the brakes (brake rotors, calipers, drums and shoes) are not connected to the moving suspension parts such as the damper spring, damper and stabilizer. Also the suspension does not require the wheels to move in order to move. You can just as easily bounce the suspension while the car is parked.
Can someone explain to me how this works?