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BRAKING BASICS & BREAK IN PRACTICE
When new pads are installed to bed them in run them through one complete heat cycle. This may vary based on the type of pad and its heat range. After one cycle has been completed allow them to fully cool before subjecting them to race conditions. It is best to bed new pads on bedded rotors, that are smooth and flat (Re-surfaced on a lathe) with no hot spots or bluing. When using new pads and rotors it requires a more delicate break in process. Heat cycling the pads once means more time for cooling the pad and rotor. Here is a practical way to bed pads. (Assuming you just installed the new pads)You should start by finding a safe location, uncrowded area preferably a track. Warm up the motor, and vehicle. Start with a series of low speed light braking manuvers to check brake system integrity, post pad install. In a closed area or safe spot start with harder stops from lower speeds 25-40 MPH. Slowly increase the speed and stopping power until they reach there specified heat range. This may be difficult to tell, a true sport pad's manufacturer will provide a heat range. After a series of 3-6 60-0MPH stops the pads should be cycled, you can always check the pad with a prod type thermometer or thermo pyrometer. When the higher speed hard stops are applied if fade is evident begin the cool down process. Slow down, avoid using the brakes, and drive until you can park the vehicle to allow the pads and rotors to reach atmospheric temperatures, before doing any racing or hard driving. Following this procedure will maximize pad life, maximize the co-efficient of friction between the materials. Now that you have that down lets get to the pedal effort you were talking about. This is called modulation. The stiffer and tighter the pedal is the less force is transfered to the clamping system via the booster and master cylinder. The higher the pressure in the brake lines and more pedal travel you have equals more force: More pedal travel=Higher system pressure/clamping force harder to modulate Stiffer pedal/tighter=Less pressure easier to modulate Modulation: The term given by the process by which the skilled driver controls the braking torque to maintain maximum retardation without locking wheels. Because the human being modulates most efficiently by force rather than displacement, effective brake modulation requires minimum pedal travel and maximum pedal firmness The pads and rotors do not change this. They may increase your systems ability to increase hydraulic pressure though. Mechanical pedal ratio: The brake pedal is designed to multiply the driver's effort. The mechanical pedal ratio is the distance from the pedal pivot point to the effective center of the footpad divided by the distance from the pivot point to the master cylinder push rod. Typical ratios range from 4:1 to 9:1.The larger the ratio, the greater the force multi- plication (and the longer the pedal travel) This ratio can be adjusted by the installer. So now you can see that brake modulation is key for controlling your braking to keep teh car stable, and has nothing to do with actual braking efficiency or braking torque.