Brembo Unveils Round 4 of World Superbike in Assen

4/16/2018

An in-depth look at the braking systems on the production-based motorcycles at TT Circuit Assen

The fourth round of the World Superbike Championship is scheduled for April 20 to 22 on TT Circuit Assen. The circuit was inaugurated in 1925 and at the time was about 28.4 km long. It was shortened to 7.7 km meter in 1955, then it underwent numerous modifications resulting in its current length of 4,542 meter. The circuit has hosted World Superbike without interruption since 1992.

Three months prior, it was the stage for Mick Doohan's fall during qualifying laps for the 500cc class. It became impossible for him to use his war-torn right leg, so the Australian used the thumb brake master cylinder designed by Brembo engineers to return to the starting grid. TT Circuit Assen stands out for its 18 corners, two thirds of which are to the right, and very short straightaways: the longest straightaway measures just 487 meter and the one at the starting line isn't more than 300 meter.

As you can imagine, this is a very drivable track that doesn't require demanding braking. This characteristic combined with the track's geographic location provide optimal conditions for cooling the steel discs. According to the Brembo technicians, who work closely with 16 World Superbike riders, TT Circuit Assen is only slightly demanding on the brakes. On a scale of 1 to 5, it earned a 1 on the difficulty index, which is exactly what Phillip Island scored.

The demand on the brakes during the GP

Just like the MotoGP riders, Superbike riders turn to their brakes on 10 of the 18 curves on the track. Only Imola, Jerez, Brno and Losail require the riders to brake more often per lap.

The brakes are used for 26 seconds per lap, which is equivalent to 27% of the overall race time.

This percentage is the same as the Round in Qatar, where the last race of the championship season will be held. Never surpassing 280 km/h, the Superbikes reach a maximum of 1.2 G in deceleration.

As a consequence, the average deceleration on the track is 1.08 G, which is among the lowest of the circuits used in the first part of the championship, together with the 1.06 G registered at Phillip Island. In Thailand, the average was 1.24 G.

The limited braking force is demonstrated by the average reduction in speed when braking: the average for the 10 braking sections is 83 km/h, the lowest in the 2017 World Championship, while in Aragon it measured 100 km/h.

Summing up all of the force applied by a rider on the brake lever from the starting line to the checkered flag, the result comes in at more than 810 kg, the same weight as 120 racing bikes.

The most demanding braking sections

Of the 10 braking sections at TT Circuit Assen, none are considered highly demanding on the brakes, but eight are of medium difficulty and two are light.

The most challenging by far is the first one after the finish line (Haarbocht Turn) because the Superbikes enter it going 276 km/h and have to lose 167 km/h before the end of the 211 meter in the braking section.

The riders use their brakes for 4.1 seconds and apply a load of 4,9 kg on the lever, which is about 2 kg less than what the MotoGP riders apply in this same corner, but they use Brembo carbon discs and calipers.

Braking at turn 16 puts greater pressure on the braking system than at turn 1: 10.8 bar compared to 10.6 bar. Both of these figures are equivalent to five times the pressure in a bottle of beer.

At turn 16, the Superbikes arrive going 208 km/h and let up on the brakes only after going down to 94 km/h, an effort that takes 3.5 seconds.

Turn 9 (De Bult) is also worth mentioning: 158 meter of braking distance, 1.2 G in deceleration and 4,3 kg on the lever to go from 277 km/h to 111km/h.

Brembo performance

Bikes with Brembo brakes won all of the last six World Superbike races at TT Circuit Assen: Jonathan Rea claimed all six victories with Kawasaki. Second place also went to motorcycles with Brembo brakes in these same four races: two for Ducati and four for Kawasaki.