Не об этом ли речь?
http://www.rallispec.com/prod_brake.htm
Anti-knockback Springs Fitted +$100
Basically forces the pad to be continuously pressed against the rotor, and to inhibit movement of the pad caused by undesired deflections under load from forcing pistons back into the caliper bores.
вот они ли это?
http://www.hrpworld.com/index.cfm?form_ ... on=product
и еще интересная ремарка:
Read about "pad knockback" for more details about why someone would want to do this. NOT something to do with a DD. At least not if you're sane!
не понимаю, почему?