This special master cylinder first saw the light of day in the 90s, thanks to a precise request made by Mick Doohan, one of the greatest champions of motorcycling history.
In the past, the rear master cylinder was often felt to be of little importance compared with the front one.
Even the professional team riders used standard products on their bikes right up to the 1990s. But over the years, as the need for less weight in the racing field increased, the idea of a lightweight but top class master cylinder for the rear wheel brake too started to seem more attractive.
The importance of this component is demonstrated by the remarkable story of the rear master cylinder that you activate with your thumb.
It was 1992, and Mick was leading the world championship when he was involved in a terrible accident during the Dutch Grand Prix on the Assen circuit. As a result of the fall, Mick suffered serious injuries to his right leg (the one used to activate the rear brake).
After a long, tough period of recovery, Mick got back on the saddle of his Honda. He did everything he could to return to the track in the best condition, but unfortunately the damage to his leg turned out to be permanent.
And so the Brembo engineers stepped in. Given Doohan’s obvious difficulty in using his leg to alter the pressure, they devised an off-the-cuff solution for activating the rear brake with a command on the left part of the handlebar, rather than the conventional right pedal method.
This was the “thumb” brake master cylinder, so-called because it’s activated by a lever that the rider pushes with his thumb.
Thanks also to this expedient, Mick Doohan was once again competitive and won 5 consecutive world championships hands down between 1994 and 1998.
Even today, many experts still uphold that the use of the thumb-activated master cylinder was a crucial factor in his amazing victories.
Applied in this way, the control of the rear brake produced a unique, personal driving style that was decisive for winning the world title five consecutive times.
In Doohan’s wake, other riders started using this method, albeit with varying results and never quite up to the same level as the Australian.
Considering that, on the track, the rear brake is often used to correct and close the path when accelerating out of a bend, the advantages of the “thumb” brake master cylinder were most likely linked to the greater sensitivity that Mick Doohan managed to apply when pressing with his thumb rather than with the tip of his right foot. Following on from this chance circumstance and making use of its long-term racing experience, Brembo subsequently paid special attention to the modular, ergonomic nature of the rear brake master cylinder.
Today, Brembo’s rear brake pumps are designed to provide the rider with the best rear braking scalability - essential for correcting the path, adjusting traction or reducing the speed on slippery surfaces.