The secrets behind the most potent part of any bike
‘Opposed-piston calipers are more robust, giving more power and feel’
Forget that high-revving 1000cc fourcylinder engine, your hydraulic disc brakes are the most ‘powerful’ part of your bike. It might take seven seconds or less to get to 100mph, but your binders will bring you to a halt in half that time as the brakes turn that energy into heat.
In a hydraulic system the braking force is proportional to hydraulic pressure placed on the brake pad from the lever or pedal, the power and feel come from different designs. The simplest caliper design, seen on mopeds and 125s, will have one or two caliper pistons on one side of the disc, using a sliding design to pull the opposing pads into contact. But a single brake pipe limits available pressure and the caliper design can flex under hard use, distorting feel.
Opposed piston calipers perform better because pressure applied to the pads and disc is equalised and the design is far more robust so that it can cope better with high hydraulic pressure. Two, four and six-piston designs allow larger pads to be used on larger discs for more power. The strongest calipers are made from a single block of metal .
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