Source: Brembo announcement
PHILIP ISLAND, Australia — After a one-week break, MotoGP starts up again in Australia where it hadn’t been held since 2019 because the country had set strict restrictions to combat the pandemic. According to the Brembo technicians who work closely with all the MotoGP riders, Phillip Island is one of the least demanding circuits on the brakes. On a scale of 1 to 6, it is rated 1 on the difficulty index.
Located on the island of the same name 140 kilometers from Melbourne, this circuit is the nearest to the South Pole in the whole championship with a latitude of 38 degrees. To keep a good initial temperature of the brakes, the MotoGPs often use carbon fiber covers, the same ones used on other circuits when it rains.
Brembo brake fluid can rise to 300 °C (572 °F) without reaching boiling point
In addition to brake calipers, discs, pads, brake master cylinders and clutch master cylinders, Brembo also supplies all the MotoGP riders with brake fluid. Two types are available: HTC64 brake fluid has higher heat resistance but lower hygroscopic properties. This refers to its ability to absorb the moisture in the atmosphere.
For this reason, if humidity is high, the brake fluid has to be replaced once a day. LFC 600 brake fluid that teams opt for when temperatures are low needs to be replaced much less frequently and is more stable in terms of compressibility and more hygroscopic. They also have different dry boiling points: approximately 315°C (599 °F) for the LFC 600 fluid and 335°C (635 °F) for the HTC64 fluid.
Brake fluids for road motorcycles
LCF 600 Plus fluid is commercially available, although it is recommended for track use: since it has a high hygroscopic level, it has a limited lifespan. This depends on several factors, but it usually ranges from 2,000 to 4000 km (1242 to 2485 miles). It can be mixed with other DOT3 and DOT4 racing fluids but should not be used in brake systems with magnesium parts.
The Brembo Sport Evo 500++ DOT4 fluid, on the other hand, has a dry boiling point of 270 °C (518 °F) and is recommended for road use without compromising performance. Its excellent properties help it to reach a high mileage before it has to be replaced, usually from 12,000 to 24,000 km (7456 to 14912 miles). However, it is not for brake systems designed for mineral fluids.
Light as a feather!
The riders use their brakes on 7 of the 12 corners on the Australian track including 3 of the first 4 after the starting line. The brake system is used for 22 seconds on each lap amounting to 25 percent of the total duration of the race. This is also due to the braking on the really slow corner 4 which is taken on at less than 70 km/h (43 mph) and takes 4.6 seconds and a 4.7 kg (12.3 lb) load on the brake lever to reduce speed by 156 km/h (97 mph).
Adding up all of the force a rider applies on the brake lever from the starting line to the checkered flag, the result comes in at just 640 kg (1410 lb), the fourth lowest in the entire championship. This combined with the proximity to the icy waters of the Pacific Ocean can cause problems with the carbon fiber brakes which risk not reaching the minimum working temperature.
To view the entire announcement, click HERE.