One might be quick to say that all of the World Superbike circuits are alike. What they have in common is the length of the races, which according to regulation falls between 85 km (52.8 miles) and 110 km (68.4 miles). Everything else is unique to each track: number of curves, mean and maximum slope, length of straightaways, undulations and type of asphalt used.
As if that isn’t enough, there are other variables that influence the efficiency of the riders and the bikes: temperature of the air and asphalt, weather conditions, and the time the race takes place. All of these factors also influence the extent to which the braking systems function. Indeed, there are tracks where the brakes are under greater stress and others where they experience very little.
However, singling out the tracks that belong to one category rather than another is not child’s play: it would be a big mistake to think that this could be based exclusively on speed.
In 2018, the best lap time in Race 1 at Phillip Island averaged almost identically to that at Buriram: 175.90 km/h (103.9 mph) in Australia, 175.10 km/h (108.8 mph) in Thailand. Even so, the first track puts the brakes under very little strain, while the second circuit is very stressful on the braking system.
The number of times the bikes brake on each track is another factor that isn’t very reliable for evaluating how much stress the braking system experiences. At Losail for example, the Superbike riders hit their brakes 13 times on the track’s 16 curves, while at Donington they brake only seven times per lap. Contrary to every prediction however, the British circuit proves much more trying on the brakes compared to the Qatar track.
Assen and Aragon are distinguished by 10 braking sections per lap, but the first track is considered easy on the brakes whilst the second falls on the other end of the scale. One of the reasons for this difference is the intensity of the braking. In the Netherlands, there is only one braking section that lasts at least 4 seconds, compared to three on the Iberian circuit.
Obviously, the force in play in a braking section taken at 300 km/h (186 mph) is not the same as braking at 200 km/h (124 mph). Although we are not dealing with tracks like Mugello and Barcelona where the MotoGP bikes surpass 345 km/h (214 mph), World Superbike still has circuits where the riders go over 300 km/h (186 mph).
If however, a track has only one braking section taken at very high speeds and others that are more contained, the stress on the braking system is decidedly less than on a track with numerous high-speed braking sections. Once again, this is best demonstrated by Phillip Island: curve number 1, which is right after the start line, is approached going 312 km/h (193.8 mph), a record in World Superbike. Yet, this is the only braking section at the Australian track which is taken at least at 230 km/h (142.9 mph).
At Imola, the bikes arrive at the Variante del Tamburello going 289 km/h (179.6 mph), the fastest for any curve on the track. Added to this section are five others that require braking from more than 235 km/h (146 mph). That explains why the circuit named for Enzo Ferrari and his son Dino out-classes almost all the other World Superbike tracks as far as difficulty.
Besides speed therefore, braking for a few dozen metres is one thing, and braking for much longer distances is another. On turn 9 at Donington and on turn 6 at Assen, the Superbikes start braking from similar speeds: 273-282 km/h (169.6-175.2 mph). However, the first scenario involves a braking distance of 209 metres and the second is a mere 95 metres (312 feet). As a result, the braking systems reach very different operating temperatures.
But even braking sections that are of the same length can strain the braking system differently if the operating load on the lever is not the same. On turn 8 at Assen and turn 6 at Imola, the Superbikes brake for 111 metres (364 feet), but the braking system reaches a pressure of 8.4 bar in the first case and 10.6 bar in the second.
Brembo technicians have kept track of all these variables, and others that are even more difficult to quantify, in order to classify the amount of stress the 13 Superbike World circuits placed on the braking systems during the 2019 season. The circuits were assessed on a scale of 1 to 5. Phillip Island and Assen scored the lowest, which translates into moderate strain on the brakes. The stress is decidedly more significant at Buriram, Imola and Donington, which is why they ranked the highest.
COMPARISON WITH MOTOGP
Superbike and MotoGP are two worlds that appear to be wildly different as regards the type of materials used and the difference in weight: the premium class prototypes weigh 157 kg (if these bikes had 800cc engines, they would weigh only 150 kg), while the production series bikes weigh 168 kg.
Nonetheless, the lap times are quite similar and the margins continue to close in: the best time ever registered at Assen by a MotoGP bike (Valentino Rossi 1’32’’627) is less than nine-tenths of a second lower than the best Superbike performance on the same track (Jonathan Rea 1’33’’505 ). At Jerez, the MotoGP advantage is one and three-tenths of a second, at Phillip Island it is one and seven-tenths of a second and at Misano it is 2 seconds.
The MotoGP bikes have more horsepower so they can accelerate faster, which means they arrive at the subsequent curve at a higher speed: on turn 7 at Losail, the MotoGP riders hit the brakes while going 218 km/h (135.5 mph), which is 21 km/h (13 mph) more than the Superbikes (197 km/h, 122.4 mph). This explains the 18 more metres (59 feet) of braking (157 metres, 515 feet, compared to 139 metres, 456 feet) done by the MotoGP bikes.
Since the Superbikes are prohibited from using carbon brakes, they are further penalised in braking times: on the first curve at Misano, the MotoGP bikes arrive going faster (271 km/h, 168.4 mph against 256 km/h, 159.1 mph) but after applying the brakes, they take the corner at a speed similar to the Superbikes (110-115 km/h, 68.4-71.5 mph). In spite of a greater loss in speed however, the MotoGP bikes activate their brakes for 3.9 seconds, which is a few tenths of a second less than the Superbikes.