MMX 370x24mm Rear 2-Piece Rotor | F8X

MMX 370x24mm Rear 2-Piece Brake Rotors – BMW F87 M2, F87 M2 Competition, F80 M3 & F82/F83 M4

Upgrade the rear braking performance of your BMW F8X M car with the MMX 370x24mm Rear 2-Piece Brake Rotors.

Designed as a direct replacement for the factory rear brake discs, the MMX rotors retain compatibility with the OEM rear calipers while introducing a lighter, floating two-piece construction with improved cooling and thermal control.

Supplied as a matched left- and right-handed pair, each 370mm x 24mm rotor uses 36 correctly oriented curved cooling vanes to help move air through the disc more efficiently.

For fast-road, track-day and performance-focused F87 M2, F87 M2 Competition, F80 M3 and F82/F83 M4 builds, these rotors are an ideal rear-axle upgrade and provide the perfect match for the MMX 380x30mm Front 2-Piece Rotors.

Why Upgrade the F8X Rear Brake Rotors?

The factory rear brake system is already very capable, but repeated high-temperature use can expose the limitations of conventional disc construction.

During fast-road or track driving, the rear brakes are subjected to:

• Repeated heat cycles
• High disc temperatures
• Stability-control intervention
• Heavy braking loads
• Sustained cornering
• Increased pad temperatures

The MMX two-piece rotor design improves heat management and allows the disc to expand more freely as temperatures rise.

This helps support more consistent braking performance and improved durability during demanding use.

Key Features

• MMX 370x24mm rear brake rotor kit
• Designed specifically for BMW F-Series M cars
• 370mm diameter
• 24mm thickness
• Two-piece floating construction
• Supplied as a matched left- and right-handed pair
• 36 directional curved cooling vanes
• Improved cooling efficiency
• Designed to run cooler than the OEM discs
• Aerospace-grade aluminium hats
• Floating bobbin mounting system
• Reduced weight compared with OEM discs
• Direct replacement for factory rear brake discs
• Compatible with OEM rear calipers
• Compatible with OEM brake pads
• Compatible with aftermarket performance pads
• Matching MMX 380x30mm front rotors available
• Suitable for road, fast-road and track use
• MMX part number MMR30-1002R

370mm x 24mm Rotor Size

The MMX rear rotors use a 370mm x 24mm specification.

This allows them to fit the compatible factory rear braking system without requiring replacement calipers or mounting brackets.

The result is a direct replacement brake disc upgrade that improves rotor construction and thermal behaviour while retaining the OEM brake architecture.

Two-Piece Floating Construction

Each MMX rotor separates the steel friction ring from the central aluminium hat.

The two components are connected using a floating bobbin system.

This allows the friction ring to expand radially and axially as it absorbs heat during heavy braking.

Compared with a rigid one-piece disc, a floating design reduces the amount of thermal stress transferred through the rotor assembly.

Potential benefits include:

• Reduced risk of distortion
• Reduced thermal stress
• Improved disc longevity
• More consistent pad contact
• Better performance through repeated heat cycles

Improved Cooling

Heat management is one of the main reasons to upgrade to a performance rotor.

MMX states that its F8X two-piece discs offer improved cooling compared with the original equipment components.

The internal vane design helps move air through the centre of the disc, allowing heat to be removed from the friction surfaces more effectively.

Better thermal control can help improve:

• Braking consistency
• Pad performance
• Rotor durability
• Brake fluid temperature management
• Track-session reliability

36 Directional Cooling Vanes

Each rear rotor uses 36 correctly oriented curved cooling vanes.

The rotors are designed as specific left- and right-hand components so the vane direction is correct on each side of the vehicle.

As the rotor turns, the curved vanes help pump air through the disc.

This improves the rate at which heat is transferred away from the braking surface.

Specific Left & Right-Hand Rotors

The MMX kit includes dedicated left- and right-handed discs.

This is important because directional cooling vanes only work correctly when installed on the intended side of the vehicle.

Correct installation helps ensure the internal cooling system operates efficiently during both road and track use.

Floating Bobbin Mounting System

The friction ring and aluminium hat are connected using floating bobbins.

These allow controlled movement between the rotor and hat as temperatures change.

When the friction ring heats up, it can expand without being rigidly constrained by the central mounting section.

This helps reduce stress and allows the rotor to remain more stable through repeated heavy braking.

Aerospace-Grade Aluminium Hats

MMX uses aerospace-grade aluminium for the central rotor hats.

This reduces weight compared with an all-steel construction while still providing the strength and dimensional stability required by the braking system.

The aluminium hat also helps isolate some of the friction-ring heat from the wheel hub.

Reduced Unsprung & Rotational Mass

MMX states that each rotor weighs less than the corresponding OEM component.

Reducing rotor weight decreases both unsprung and rotational mass.

Potential benefits can include:

• Improved suspension response
• Reduced rotating inertia
• More responsive chassis behaviour
• Reduced overall brake assembly weight

Although thermal performance remains the main reason for the upgrade, the weight reduction is a useful additional advantage.

Grooved Friction Surface

The MMX rear discs use a grooved friction surface.

These grooves help clear gases and debris from the pad face while providing consistent contact between the pad and rotor.

The design is intended to balance:

• Initial bite
• Brake feel
• Pad cleaning
• Rotor longevity

The matching front MMX discs use the same visual and performance-oriented groove design, allowing both axles to be upgraded as a cohesive system.

Direct Fit with OEM Rear Calipers

The MMX rear rotors are designed around the original BMW rear calipers.

No aftermarket caliper or mounting bracket is required for compatible applications.

This makes them an attractive upgrade for owners who want better rotor performance without changing the complete braking system.

OEM & Aftermarket Pad Compatibility

The MMX rear rotors can be used with:

• OEM BMW pads
• Fast-road performance pads
• Track-focused pads
• Compatible aftermarket pad compounds

This gives owners the flexibility to tune the braking system to the intended use of the car.

Ideal Match for MMX Front Rotors

MMX offers matching 380x30mm front two-piece rotors for the F8X platform.

Combining the front and rear kits provides:

• Matching two-piece construction
• Improved cooling across both axles
• Matching groove pattern
• Reduced brake rotor weight
• More complete thermal management
• Consistent appearance

For owners upgrading the complete braking system, using matching MMX rotors front and rear creates a cohesive setup.

Better Braking Consistency

Performance brakes are about more than peak stopping force.

Consistency becomes especially important on track.

As rotor temperature rises, the behaviour of the disc, pad and brake fluid can all change.

Improved rotor cooling can help create more stable operating conditions and maintain more predictable braking throughout a session.

Fast-Road Benefits

For a fast-road F8X, the MMX rear rotor upgrade retains OEM-style functionality while improving:

• Heat management
• Rotor durability
• Brake feel
• Weight
• Appearance

This makes the kit suitable for cars that are used predominantly on the road but regularly driven hard.

Track-Day Benefits

On circuit, the rear brakes can see more work than many drivers expect.

Modern BMW stability and differential-control systems can use the rear brakes dynamically in addition to conventional braking loads.

During repeated hard use, improved rotor cooling can therefore be particularly valuable.

The MMX two-piece design is well suited to:

• Track days
• Fast-road use
• Clubsport builds
• Semi-slick tyre setups
• High-power cars

Ideal Supporting Upgrades

For maximum benefit, consider combining the MMX rear rotors with:

• MMX 380x30mm front two-piece rotors
• Performance brake pads
• High-temperature brake fluid
• Braided brake lines
• Brake cooling upgrades
• Performance tyres

A braking system should ideally be treated as a complete package.

BMW F87 M2

The MMX 370x24mm rear rotor kit is compatible with the BMW F87 M2.

For N55-powered M2 builds, the rotors provide improved rear brake thermal control while retaining the factory calipers and pad format.

BMW F87 M2 Competition

The MMX rear rotor kit is also compatible with the BMW F87 M2 Competition.

The higher-output S55-powered M2 Competition can place substantial demands on the braking system during fast-road and track use, making improved rotor construction and cooling particularly worthwhile.

BMW F80 M3

The rotor kit is compatible with the BMW F80 M3.

For track-focused or high-performance road builds, it provides a direct-fit route to improved rear rotor thermal management.

BMW F82 M4

The MMX 370x24mm rear rotors are suitable for the BMW F82 M4.

They retain the compatible factory rear calipers while upgrading the disc construction and cooling capability.

BMW F83 M4 Convertible

The kit is also compatible with the BMW F83 M4 Convertible.

The same floating two-piece construction provides improved thermal performance for demanding road and track-style use.

Compatibility

Designed for applicable BMW F8X M cars including:

• BMW F87 M2
• BMW F87 M2 Competition
• BMW F80 M3
• BMW F82 M4
• BMW F83 M4 Convertible

MMX lists the application for F80, F82, F83 and F87 chassis with N55 and S55 engines.

Please confirm the existing brake specification on your vehicle before ordering.

What's Included?

The MMX 370x24mm Rear 2-Piece Rotor Kit includes:

• 1x left-hand 370x24mm two-piece floating rear rotor
• 1x right-hand 370x24mm two-piece floating rear rotor
• Aerospace-grade aluminium hats
• Floating bobbin assemblies

Supplied as a complete rear axle pair.

Explore More BMW F8X Brake Upgrades

Looking to improve your F8X braking system further? Explore our range of performance brake components.

BMW F87 M2 Parts – Shop braking, suspension and performance upgrades for the BMW F87 M2.

BMW F87 M2 Competition Parts – Browse braking and chassis upgrades for the BMW F87 M2 Competition.

BMW F80 M3 Parts – Explore performance brake products for the BMW F80 M3.

BMW F82 / F83 M4 Parts – Browse braking and chassis upgrades for the BMW F8X M4.

MMX Performance – Explore MMX braking, suspension, drivetrain and performance upgrades.

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