Separate circuits. With the exception of paragraph 2) below, the complete braking system is free provided it incorporates at least two separate circuits operated by the same pedal. This system must be designed so that if leakage or failure occurs in one circuit, the pedal shall still operate the brakes on at least two wheels. The brake fluid tanks may be fixed inside the cockpit, on condition that they are securely fastened and protected. The balance of the braking forces between the front and rear axles may only be adjusted by the driver, through : - direct and manual intervention on a mechanical system allowing the modification of the position of the centre of the joint, on the linkage lever of the hydraulic pumps of the front and rear circuits. - direct and manual intervention on a proportional valve, in which the intake pressure of the rear circuit is adjusted through a pre- loaded spring, variable according to the position of the manual linkage system (see the drawing of the principle 263-9). Only one of these two systems is permitted.
