Disc brakes help bikes have consistent stopping power in a variety of weather conditions. While rim brakes and disc brakes perform about the same and dry in normal conditions, anyone that’s ridden in the rain knows that rim brakes lose stopping power when conditions get wet. This can be especially terrifying when you’re going fast. For mountain bikes, wet conditions are par for the course. And so having brakes that work well in these conditions is vital to safety. helps with fatigue, and makes the experience more enjoyable overall. But what is the difference between mechanical and hydraulic disc brakes?
Mechanical Disk Brakes
Mechanical disc brakes use a physical brake cable attached to actuate the brakes. This cable pulls the caliper, squeezes the brake pads on the rotor, and causes you to slow down. Most entry-level bikes with disc brakes will have a mechanical disc brake system.
Hydraulic Disk Brakes
Hydraulic disc brakes, on the other hand, use a hollow brake line that is filled with brake fluid, much like your car, to activate the caliper. You will find hydraulic brakes on most mid to upper-level bikes.
The Difference
The analogy that all used to compare these two systems is running in the sand versus running on concrete. Running in the sand is more difficult because you’re losing energy every time you take a step. The same is true for hydraulic mechanical disc brakes. When you pull the cable, you’re losing energy due to the stretch of the cable. This means you have to squeeze the brake harder to achieve the same stopping distance. Over the course of a long ride, this can cause significant fatigue especially when you’re riding in steeper terrain. Hydraulic disc brakes transfer virtually all of your force into the brake pad. This is why you only need to use one finger to squeeze the brakes and a hydraulic brake system. For those that have ridden with hydraulic brakes, you know the feeling.
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