כן זה גם מה שאני מכיר.. הוא רשם אח"כ:
is not air bubble , is vapor bubble , if you don't change the brake fluid for some years some humidity can get into the fluid , if the caliper is poorly maintained there is some friction
between the rotor and the caliper , this generate heat , and the water turns to vapor locking the brake
בקיצור כנראה תירוץ או משהו.