The master cylinder is a control device that changes non-hydraulic pressure from a driver’s foot into hydraulic pressure.in doing this, it controls another component called the slave cylinders located at the other end of the system.
As pistons passes along the bore of the master cylinder, this movement is translated through the master cylinder to a movement of the slave cylinder(s) through the hydraulic fluid. The pressure created by moving a piston toward the slave cylinder(s) forces the fluid evenly.
The most common
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