What?: A disc brake system with the dual-diameter opposed-piston caliper design has differently sized pistons in front and in the rear. The system adopts a power transfer system in which the disc brake rotor is pressed by the smaller sized piston at the entrance of the disc brake rotor intake and also by the more powerful larger sized piston at the back. This prevents the wobbling motion of the disc brake rotor and reduces noises significantly.
The 4-piston caliper also allows a wider contact area for the disc brake rotor while keeping the size compact, and the efficient location of pads is adjusted as necessary to stabilize the pressure.
Who?: Those riders looking for more gnarly trails, more emphasis on the downhills, and more braking power. Trail riders and Enduro racers rely on these powerful 4-pots. Think Martin Maes and Jill Kiltner.
Where?: The 4-pot brakes come into their own when the mountains call. Long, steep trails that require constant and consistent powerful braking.
When?: When stopping power is paramount and weight is not decisive. When you’re not sure when the end of the downhill will come but you need to know that your brakes will still be working faultlessly by then!
Why?: The reason you would want 4-pot brakes is power! You need power if you’re a heavier rider on a heavier bike experiencing bigger speeds over longer descents.