My bike is equipped with disk-brakes. It also has a fork with suspension.
When I apply the front brake, my fork vibrates violently, as can be seen below:
I've adjusted the brake-pads, the cable is in good working order.
Is this shudder caused by a faulty brake or a faulty fork?
The shaking happens at any speed, by the way, and any brake-pressure (other than feather-light brake.)
brake is Shimano, cable-operated.
bike is eWind classic.
fork is TGs 068E "Top Gun."
UPDATE:
When flipped upside down, the braking seems fine, but I am not sure if this is a fair comparison? When riding, the inertia of forward moving mass of the bike will resist the brake. When on ground, there is no such force.
There is no free play in the steering head or fork tubes, that I can see.
The wheel is true.
The calipers are securely fixed to the frame.
UPDATE 2:
The test suggested by @andrew-hendle:
UPDATE 3:
I investigated this some more, and closely watched the shaking fork while I'm riding and braking.
It turns out that top-side, at the frame, the fork is perfectly still.
Only the bottom-end of the fork, at the wheel, does it violently shake, forwards, and backwards.