BMW M Carbon Ceramic Brakes – The Complete Guide

BMW M Carbon Ceramic Brakes at a Glance

• What are M Carbon Ceramic Brakes?
• Cost of the M Carbon Ceramic Brakes
• Why are the M Carbon Ceramic Brakes Expensive?
• M Carbon Ceramic Brakes Versus M Compound Brakes
• M Carbon Ceramic Brake Disc Design and Special Features
• Front Axle of the M Carbon Ceramic Brakes
• Rear Axle of the M Carbon Ceramic Brakes
• Technical Data on the M Carbon Ceramic Brakes
• Advantages of the M Carbon Ceramic Brakes
• Anti-Corrosion Property of the M Carbon Ceramic Brakes
• Braking Performance and Effect of the M Carbon Ceramic Brakes
• Cleaning and Care of the M Carbon Ceramic Brakes
• M Carbon Ceramic Brakes on the Race Track
• M Carbon Ceramic Brake Pad Wear and Tear

What are M Carbon Ceramic Brakes?

M Carbon Ceramic brakes are made from durable carbon compound ceramic materials to withstand extreme temperatures from the high-performance demands of the track. Also known as the BMW C/SiC (Carbon Fiber Reinforced Silicon Carbide) Brakes, the M Carbon Ceramic Brake discs are fabricated from carbon fibers. The brake calipers are painted in eye-catching gold adorn with the signature BMW M logo. The brake discs are manufactured by Brembo SGL Carbon Ceramic Brakes GmbH.

Cost of the M Carbon Ceramic Brakes

The M Carbon Ceramic Brakes can be added to selected BMW M models for an additional $8,500 to $9,250 as a Performance Option. 20-inch or greater M wheels must be ordered in conjunction with the M Carbon Ceramic Brake option on your new BMW. This is because the brake discs are larger on the front wheels and cannot fit into the stock wheels provided.

Why are the M Carbon Ceramic Brakes Expensive?

The production process of the Carbon Ceramic Brakes involves siliconizing the friction ring for 24 hours at 1,300 degrees. Then the carbon fiber-reinforced silicon carbide brake disc has a construction and development time of several weeks.

The production time spent and constructional materials needed are the leading causes which drove the M Carbon Ceramic Brakes retail price higher than conventional brakes. However, the price is justifiable as these brakes can endure much higher levels of wear and tear compared to the conventional brakes

M Carbon Ceramic Brakes Versus M Compound Brakes

The M Carbon Ceramic Brakes are lighter and better in performance than the M Compound Brakes or the conventional brakes.

Compared to the M Compound Brakes, the most significant advantage of the M Carbon Ceramic Brakes is their lightweight property. M Carbon Ceramic Brakes is 12.5 kg (about 27 pounds) lighter in rotating mass than the standard M Compound Brakes. The M Carbon Ceramic Brakes also offer more stability because the operational surface of the brake pads is significantly higher.

M Carbon Ceramic Brake Disc Design and Special Features

The M Carbon Ceramic Brake disc body can have visible cracked patterns (relaxed microstructure). This is typical for the M Carbon Ceramic Brake disc, and the cracks can remain visible during normal drive.

M Carbon Ceramic Brake Disc Components and Materials

The BMW M Carbon Ceramic Brake discs are made up of the following two types of materials:

1. The support body with the cooling ducts has a sintered silicon carbide ceramic base that is reinforced with a high content of carbon fiber direction-oriented strands.
2. The inner and outer friction coating has a much higher ceramic content.

M Carbon Ceramic Brake Disc Engravings

The M Carbon Ceramic Brakes have the following information engraved on the front and rear axle brake disc hubs:

• Serial number
• Part number
• Direction of travel
• Minimum weight (wear weight)
• Minimum thickness (wear thickness)
• Week/year of manufacture

Front Axle of the M Carbon Ceramic Brakes

Front Axle Brake Discs

The front axle brake disc hub is made of high strength aluminum alloy.

The friction ring width (swept area) of the front M Carbon Ceramic Brake disc is 88.8 mm (about 3.5 inches). This is larger than the M Compound Brake disc, which measures 76 mm (about 3.0 inches).

The diameter of the M Carbon Ceramic Brake disc is 410 mm (about 16.14 inches), and its thickness is 38 mm (about 1.5 inches).

Front Axle Brake Caliper/Pad

The M Carbon Ceramic Brake caliper at the contact surface of the swivel bearing is 5 mm (about 0.19 inches) less than the M compound brake caliper. This is because the Carbon Ceramic Brake disc has a 5 mm larger radius and friction ring.

Overall, the weight of the front brake caliper including the brake pad is 0.4 kg (about 0.88 lbs) heavier than the M Compound Brake caliper.

Rear Axle of the M Carbon Ceramic Brakes

Rear Axle Brake Discs

The rear axle brake disc hub is manufactured with high strength aluminum alloy, which is the same as the front axle brake disc hub.

The rear M Carbon Ceramic Brake disc has the same diameter as the M Compound Brake disc. However, the thickness is 2 mm (about 0.78 inches) greater.

Rear Axle Brake Caliper/Pad

The size of the M Carbon Ceramic Brake rear axle caliper and brake pads are the same as the M Compound Brakes.

Technical Data on the M Carbon Ceramic Brakes

Advantages of the M Carbon Ceramic Brakes

The M Carbon Ceramic Brakes are highly durable, lightweight, and has a much longer lifespan compared to the conventional brakes.

Here’s is a list of Advantages of the M Carbon Ceramic Brakes

• More direct and spontaneous use of brake force
• High fading stability and resistance
• Large 16-inch front rotors
• 19.4 kg (about 42 lbs) weight reduction of the unsprung rotational wheel masses
• Brake pad lifespan lasts 2-3 times longer than conventional brakes
• Rotor lifespan lasts 3-4 times longer than conventional brakes
• Increased reliability for winter driving conditions with corrosion resistance

Anti-Corrosion Property of the M Carbon Ceramic Brakes

BMWs with conventional brake discs that have not been driven for an extended period and has low mileage, corrosion can take place. This is because the minimum load level required to start a brake disc’s self-cleaning mechanism cannot be reached.

The M Carbon Ceramic Brake discs are not as susceptible to corrosion because rust films do not form on the friction ring constructed from grey-cast iron. In addition, the new M Carbon Ceramic Brake disc’s friction surface is covered with a stress-relief coating.

Braking Performance and Effect of the M Carbon Ceramic Brakes

Cleaning and Care of the M Carbon Ceramic Brakes

When taking your BMW with M Carbon Ceramic Brakes to a car wash, it is important to clean both brake discs and calipers with a steam jet or high-pressure cleaner. This prevents the formation of encrustations or deposits of salt crystals when the car is parked after cleaning.

If wheel cleaner is used, make sure it is only applied to the wheel rims and does not touch the brake discs or the calipers.

Use a wheel cleaner that is acid-free and pH balanced, which is safe on the BMW standard alloy and aluminum rims. If you have custom wheels with powder/decorative coating or any other special materials, be sure to check if the solution is safe for the material. Use a brush with extra-soft and scratch-free bristles to detail the rims if safe and necessary but avoid the brakes. Dry the wheels with a soft, lint-free, and non-scratch microfiber cloth that does not harm the wheel surface. You can go one step further by cleaning the tires separately with a non-toxic, environmentally-friendly tire dressing care and microfiber cleaning pad.

M Carbon Ceramic Brakes on the Race Track

On the race track, the M Carbon Ceramic Brake discs may be subject to oxidative wear when the discs are repeatedly heated to temperatures of 600 degrees and over due to hard braking effects. As a result, the fibers within the brake discs can burn and will up become lighter, not thinner.

M Carbon Ceramic Brake Pad Wear and Tear

After about 1,000 km (approx. 621 miles) of driving, the brake discs and pads can achieve favorable wear and contact pattern.

With silicon carbide friction coating on the M Carbon Ceramic Brake pads, the brake pads will wear out very slowly under normal (ideal) driving. The M Carbon Ceramic Brake disc should last through the lifespan of the car itself since the silicon carbide friction coating is nearly non-wearing.

The racetrack, however, can wear out the brake discs faster. As mentioned earlier, when the M Carbon Ceramic Brake discs are frequently heated to temperatures of 600 degrees or higher, the brake disc fibers can burn up sooner and result in oxidative wear.

M Carbon Ceramic Brake Disc Wear Characteristics

Comparing to the M Compound Brake Disc, the M Carbon Ceramic Brake disc has a much longer lifespan and can last the service life of the vehicle in ideal everyday driving. Over time, oxidation of the carbon fibers and sporting driving styles can cause the brake disc to lose weight and strength.

Four Wear Indicators of the M Carbon Ceramic Brake Disc

There are four indicators to check for signs of wear on the M Carbon Ceramic Brake disc:

1. Check the disc surface for visible signs of wear and damage
2. Three wear indicators are appearing as dark circular spots per friction surface located at every 120 degrees on the disc. When these indicators are subjected to high levels of oxidative wear, these wear indicator marks will become exposed
3. Minimum permitted brake disc weight should be 7954 g (about 17.5 lbs)
4. Minimum brake disc thickness should be 37.85 mm (about 1.49 inches)

Why is the Cool-Down Lap Important for the M Carbon Ceramic Brakes?

After driving with high speed or on the racetrack, it is essential for the M Carbon Ceramic Brakes to cool down with the airstream. If your BMW is parked while the brake discs are close to 500 degrees, heat can transfer throughout the brake system and damage brake pads, back plate, damping plates, brake calipers, piston seals, and the dust shields.

By performing a cool-down lap, the airstream can bring the temperature of the M Carbon Ceramic Brake discs down below 200 degrees.

Wet M Carbon Ceramic Brakes

Although the braking power of the M Carbon Ceramic brakes is applied precisely in all weather conditions due to the brake material’s strength and durability, when driving in the rain, during wet road conditions, or right after a car wash, the M Carbon Ceramic Brake discs and pads will experience a drop in their friction coefficient value. The braking effect may be equivalent to that of a conventional brake system when impacted by moisture and road salt.

This can be compensated by applying more pressure on the brakes until the pads and discs have dried out completely. At times, wet M Carbon Ceramic Brakes can cause an audible operational noise when the car brakes towards a stop. However, this does not affect the brakes’ performance, operational safety or stability.