KN Auto Engineering Inc.

What design feature causes the valve lifter to rotate?

ELECTRONIC BRAKE FORCE DISTRIBUTION ( EBD ):

Electronic brake-force distribution (EBD or EBFD) is an automobile brake technology that automatically varies the amount of brake force applied to each of a vehicle's wheels, based on road conditions, speed, loading, etc.

EBD is an added function to the ABS (Anti-lock Brake System) and
it is based on the principle that the weight being supported by the wheels of your car isn't evenly distributed.

Some wheels carry a heavier load than others and will require more brake force in order to bring the car to a stop without it going out of control.

Furthermore, the amount of weight being supported by a wheel shifts during the braking process, so the amount of force necessary at each wheel can change rapidly.

An EBD system can not only detect how much weight is being supported by each wheel, but change the amount of braking power sent to each wheel on an instant-by-instant basis.