WARNING: This product can expose you to chemicals that are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information, visit www.P65warnings.ca.gov.These GiroDisc 2-piece rotors are a direct replacement for the front rotors on the B9 S4, S5, and SQ5. Our 2-piece, fully floating assemblies help shed unsprung weight and rotating mass from the front axle of the vehicle.
The rotor rings are machined from a proprietary casting made of high-carbon iron formulated to GiroDisc’s specifications. This superior metallurgy results in a rotor that holds up better, and the 72 curved vanes act as a centrifugal pump pulling air in through the hub to effectively cool the rotors under hard use. The 2-piece design means a reusable hat which can be attached to new rings (part number D1-311) when they need to be replaced.
All major components including the hats, rotor rings, and drive pins are manufactured in-house at our facility in Bellingham, WA from domestically sourced materials. The hat is made from 6061-T6 aluminum and coated in a black anodize finish. The drive pins are made from a high-strength steel alloy and cadmium-plated for corrosion resistance. All rotors are assembled with spring clips and Belleville washers for race-ready float while also being street-friendly with no noise from loose hardware.
The minimum thickness at which we recommend replacing these rings is 32mm. We also recommend replacing them if a crack leads to the edge of the ring.
