Shimano Deore XT Ice-Tec Centre Lock Rotors SM-RT81 180mm. Ice-Tech: The Shimano SM-RT81 Ice-Tec disc brake rotors give excellent performance due to the stainless steel/alloy 3-layer sandwich construction which provides excellent heat management. Shimano’s proven Centre-Lock system combines excellent rigidity and security with an easy set-up. These brake discs are ideally suited to Shimano Deore XT disc brake systems but Can be used on other models. The clad steel / alloy / steel rotor construction allows heat generated from braking to radiate quickly through the aluminium core achieving surface temperature drops of around 50 deg C. When used with Ice-Tec pads surface temperatures can drop from around 400 to 300 deg C, this provides great improvements in all round performance. Due to this improved heat dispersion, Ice-Tec rotors achieve longer pad life, less noise and less fade. A large forged alloy spider supports the rotor surface, increasing rigidity and reducing weight. Comes complete with alloy lockring. NB: Image for illustration purposes only – supplied as single rotor only.