Joalo ka ha li-rotor tsa brake li entsoe ka tšepe, ka tlhaho lia rusa 'me ha li pepesehetse liminerale tse kang letsoai, mafome (oxidization) a atisa ho potlakisa.Sena se u siea ka rotor e shebahalang e le mpe haholo.
Ka tlhaho, lik'hamphani li ile tsa qala ho sheba litsela tsa ho fokotsa mafome a rotor.Tsela e 'ngoe e ne e le ho sebelisa lesela la Geomet ho thibela mafome.