MMX Performance F8X 2-Piece 370mm Floating Rear Rotors M2 M3 M4

The MMX 2-Piece 370mm Floating Rear Rotor Set completes the F8X rotor upgrade started by the matching MMR30-1001F front set. Designed and tested by MMX as a direct replacement for the OEM iron rear disc, this is a true two-piece floating rotor (left- and right-handed specific) built to drop the OEM rotor's heat-induced limitations without any caliper or hub modification.

Each rotor pairs a proprietary high-carbon iron friction ring with a CNC-machined 6061-T6 aircraft-specification aluminium hat, connected by a floating bobbin system. That floating mount allows full radial and axial thermal expansion as the rotor heats, eliminating the warping and surface cracking that single-piece OEM discs suffer under repeated heavy braking. The aluminium hat reduces unsprung and rotational mass at the rear axle for improved ride and traction control response.

The friction face is laid out with 36 directionally curved cooling vanes that act as a centrifugal pump as the rotor spins, drawing air through the centre of the disc and out through the friction ring. MMX states the assembly delivers up to 30% improved cooling efficiency over the OEM rear rotor, translating directly into less rear-axle fade on track, more consistent pad release behaviour, and longer rotor life across track-day cycles. MMX's signature directional grooves on the friction surface improve initial bite and clear pad gases and debris from the pad face.

This rotor uses the OEM rear caliper that came on F80 M3, F82/F83 M4, and the original N55-engined F87 M2, and it accepts OEM or upgraded MMX RP650 brake pads. It is engineered as the matching rear pair to the MMR30-1001F front set, completing a full F8X iron rotor upgrade.

Product Details

• Diameter × thickness: 370mm × 24mm
• True 2-piece floating construction with floating bobbin mounting system
• Proprietary high-carbon iron rotor ring with directional groove pattern
• 6061-T6 aircraft-specification aluminium hat (CNC-machined)
• 36 directionally curved internal cooling vanes
• SKU: MMR30-1002R

What's Included

• 1× pair of 2-piece floating rear rotors (left + right directional, 370mm × 24mm)
• Floating bobbin hardware pre-installed
• Brake pads not included: sold separately

Vehicle Applications

• BMW M2 (F87)
• BMW M3 (F80)
• BMW M4 (F82 / F83)

Related Products

• MMX F8X 2-Piece 380mm Floating Front Rotor Set
• MMX RP650 Performance Front Brake Pads F8X

Notes

• NOT confirmed for F87 M2 Competition or M2 CS. Authorized-dealer copy explicitly markets this product for "M2 (non-Competition)." The M2 Competition / M2 CS use the same S55 M3/M4 rear hardware platform but exact rotor specification has not been confirmed by MMX, please verify directly before ordering.
• NOT compatible with the M Carbon Ceramic Brake (CCB) package. CCB cars use a carbon-ceramic friction surface and CCB-specific calipers.
• Discs are directional: left- and right-handed specific. Verify orientation before installation.
• Sold as a pair. Pair with MMR30-1001F front set for a complete F8X rotor refresh.
• Brake pads are sold separately. Consider MMX RP650 rear pads (MMR27-0501R) for a matched fast-road brake setup.
• Includes a 1-year manufacturer warranty against defects in materials and workmanship
• Designed and tested in the United Kingdom