Replacement rotor friction rings with hardware for the rear Girodiscs rotors on G20 M340i, G22/G26 M440i, G30 5-series, G12 7-series (and Alpina B7), G01 X3 M40i, G02 X4 M40i, G29 Z4 M40i, and A90/GR Supra. These are the cast iron rings only and you must already have the Girodisc center hat.
Girodisc (guy-ro) rotors are made for track/race cars as part of a two-piece disc + hat assembly. Keep the aluminum hat and only replace the cast iron friction ring. New hardware is included with new rings. Girodisc rings are cast in the USA from their own proprietary cast iron, cadmium plated for corrosion resistance, and then painstakingly machined and balanced in the USA.
Two-piece rotors are standard equipment on race cars thanks to weight savings and improved cooling. The rotor has a curved inner vane configuration that works like a centrifugal pump to force air through the rotor. If you're not yet ready to jump up to a larger big brake kit, the Girodisc is the next best thing. With it's two-piece and serviceable design, you can improve on the stock braking system performance without having to commit to larger, heavier, and costlier brake kits.
Girodisc has nearly 20 years of experience as a brake disc supplier to major international race teams and series. Originally manufacturing replacement rings for racing brake kits from Brembo, StopTech, and others, they now supply direct-replacement rotor upgrades for OEM brake systems. All material and components are sourced from the USA with Girodisc doing all of their machining in-house. While also offering other niche products, rotors are their primary product which guarantees excellent quality and satisfaction.
Price is for the pair of friction rings with hardware.
BMW Fitments:
3 Series
G20 (2019+) > M340i
G20 (2019+) > M340i xDrive
4 Series
G22 / G23 (2021+) > M440i
G22 / G23 (2021+) > M440i xDrive
4 Series
G26 (2022+) > M440i xDrive Gran Coupe
5 Series
G30 (2017-2022) > 530i
G30 (2017-2022) > 530i xDrive
G30 (2017-2022) > 540i (B58A 2017-2019)
G30 (2017-2022) > 540i (B58C 2020-)
G30 (2017-2022) > 540i xDrive (B58A 2017-2019)
G30 (2017-2022) > 540i xDrive (B58C 2020-)
G30 (2017-2022) > M550i xDrive N63R (17-19)
G30 (2017-2022) > M550i xDrive N63T3 (2020+)
7 Series
G12 (2016+) > 740i
G12 (2016+) > 740i xDrive
G12 (2016+) > 750i
G12 (2016+) > 750i xDrive
8 Series
G14 / G15 (2019+) > 840i xDrive
X3 Series
G01 X3 (2018+) > X3 M40i
X4 Series
G02 X4 (2019+) > X4 M40i
Z Series
G29 Z4 (2019+) > Z4 M40i