MotoGP riders are on the brakes for 33% of a lap at Jerez, the highest of any track on the MotoGP schedule.
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Everything you need to know about the demands on the braking systems mounted on the bikes ridden by the entire field
With the three non-European rounds out of the way, MotoGP heads to Spain for the fourth round of the 2017 season at Circuito de Jerez, May 5-7.
The circuit opened on December 8, 1985. The track has hosted the premier class since 1987. Oddly enough, however, in 1988 the race was labeled the Portuguese GP because the Spanish GP was held in Jarama.
In 1992 it became the first track in the championship to replace the hay bales with airfences. The 2.748-miles of the track alternate between slow, fast and very fast corners. The 13 turns (eight right-handers and five left-handers) represent 31 percent of the total length and provide numerous places for passing.
The significant changes in slope demand a bike that handles well and that is well balanced, in addition to being stable in braking.
Once again this year, 100% of the bikes participating in the MotoGP championship are equipped with Brembo brakes and Brembo’s engineers have assigned a difficulty index for the brakes to each circuit on the calendar.
According to the Brembo engineers who assist all the MotoGP riders, the Circuito de Jerez is the most demanding track on brakes in the first third of the season, in other words, out of the first six Grand Prix races. On a scale of 1 to 5, it earned a four on the difficulty index, the same score as Aragon and Brno.
On every lap, the riders will have to use the brakes 11 times for a total of 33 seconds. In absolute terms, that is not excessively high, especially if compared with the 38 seconds per lap at Austin and the 37 at Losail. However, on these two tracks, the lap records range from 1’55” to 2’05”, whereas at Jerez lap times are 1’39” and that gives the Spanish track the highest percentage in the championship of time spent braking: 33 percent.
The presence of three moderate braking sections, in other words, with less than a 22 mph drop in speed, translates into an average race deceleration of just 2.359 lbf (pounds of force). Lowering this average are the values of 1.543 lbf. on turns four and seven and 1.764 lbf. on Turn 10. Only Austin, with 2.028 lbf., has a lower average value.
Adding up all the force the rider applies on the Brembo brake lever from flag to flag, the value is greater than 1.543 tons, a value that Losail and Valencia also reach. In practical terms, on each lap, the rider has to apply a force of 114.6 lbs.
Of the 11 braking sections on the Circuito de Jerez, two are classified as demanding on the brakes and five are of medium difficulty. The remaining four have a low impact on the braking systems.
The most complicated braking section is on the first turn (Expo 92) that comes after a 656 yard straight, which is the longest on the track. The riders begin to brake at 174.6 mph and complete the operation only after 4.6 seconds, during which they cover 239.5 yards. In order to drop to 53 mph, they apply a load of 15.21 lbs. on the brake lever and undergo maximum deceleration of 3.307 lbf.
Braking operations on turn six (Dry Sack) are also quite difficult. The MotoGP bikes go from 182.1 mph to 40.39 mph in 275.6 yards and 5.5 seconds. However, the load on the lever (14.55 lb) is lower, as is the pressure of the Brembo HTC 64T brake fluid (166.8 psi) and deceleration is 3.086 lbf., which is 0.4409 lbf. higher than the 124.3 to 0 mph of a Porsche 993 Turbo.
Also noteworthy are the braking system’s 147.9 psi on the second turn, the equivalent of about 7 times the pressure of beer on tap. The MotoGP bikes brake for 3.3 seconds to set up the turn at 41 mph, but the deceleration is only 2.425 lbf.
Brembo brakes have won 26 out of the 38 Spanish GP editions, including the last 23. Yamaha has won the last two editions, but Honda boasts no less than 16 wins with Brembo brakes. This year, Valentino Rossi is chasing his 10th win at Jerez. He won in 1997 in the 125 class, in 1999 in 250, in 2001 in 500 and 6 times in MotoGP. Each time he won, he was using Brembo brakes.
Click the image below to see these braking facts in gif form.