A reliable brake often makes the difference between victory and defeat. Response and friction coefficient, metering, wear, fading stability and temperature behavior should be optimally matched to the application, the vehicle and, not least, the driver’s preferences. The selection of different brake pad qualities is enormous, especially for common motorsport calipers, and accordingly finding the optimum combination involves a lot of testing. But the best brake pad can only function optimally if it has been properly braked in. This is a topic that is often neglected, so let’s take a closer look.
The correct running-in of new high-performance brake pads is a prerequisite for a long service life and the correct braking effect. But why brake in at all? First of all, it is a matter of surface alignment of the brake pad and disc. In addition, a first layer of friction material is placed on the disc to have better performance. And certain components required for production are “burned out” during braking.
It should be noted that, if possible, no new brake discs should be fitted during the braking phase. If a different lining material was previously used on the old discs, it is recommended to clean the discs with sandpaper. The brake pads must sit freely and without jamming in the brake calipers. By the way, the reverse is also true: new brake discs should always be braked with the pads on.
Most brake pads available on the market have an organic-based friction lining with certain metallic and/or ceramic components. The braking process takes place in 3 steps. First, the surfaces of the brake disc and brake pad must be matched. To do this, brake approx. 10 times at medium brake pressure from approx. 150 to 80 km/h. There should be approximately 600 to 800 meters between each braking operation. The next step is to bring the braking system up to temperature. To do this, brake approx. 5 times with medium to high brake pressure from approx. 180 to 60 km/h (without ABS triggering). Accelerate to the maximum between braking processes and then allow the brake to cool down for 3 minutes at approx. 100 km/h. In the last step for pad cleaning, brake with light brake pressure from 150 to 80 km/h, then let the brake cool down 600 to 800 meters and repeat the procedure 4-5 times. After this, allow the brake to cool down in a run-out lap, and the pad can then be loaded normally.
The procedure is different for sintered metal brake pads (the best-known manufacturer here is CL-Brakes). These do not require thermal braking (i.e. gradual heating and cooling as described above) but only mechanical braking. For this purpose, the brakes are applied only a few times from medium speed, so that the surfaces of the pad and disc can adapt to each other. This procedure is very simple and can theoretically be done directly in the outlap (on the circuit) or the liaison stage to the first special stage (in rallying).
Some pad manufacturers (such as Pagid Racing) now also offer factory-braked brake pads. These are run in on the test rig with programs individually tailored to the respective pavement quality, thus saving the motorsport team time and money. The break-in process on the race track is then as simple as with sintered metal linings.
By the way: correct braking is also very important for brake discs. And this happens somewhat differently than with brake pads, which is why, as already mentioned at the beginning, discs and pads should not be braked in together if possible. Motorsport discs are braked in over approx. 30 km to prevent premature cracking. Brake gently from low speed for the first 15 km, then increase speed to maximum for another 15 km but still do not brake hard. At the end of the run-in distance, the brake can then be loaded hard 2-3 times. The disc temperature should reach around 450 to 500°C. After running in, allow the brake discs to cool down completely.
