Choosing the right brakes for your mountain bike is a piece of cake–if you know what to look for. If you’re in the market to upgrade your bike’s stoppers, this guide should dial you in to what’s important.
Mountain Bike Brake Types
There are effectively 3 types of brakes you’ll find on mountain bikes, though really only one type–disc–should be under consideration for most folks. In general, mountain bike frames are set up to handle either a disc or rim-style brake so be sure to determine which mounts you have before choosing an upgrade.
Coaster brakes: Remember skidding your bike in the driveway as a kid? If so, your bike probably had coasters which lock the rear wheel when you back-pedal. The very first mountain bikes had these and believe it or not, they’re making a (very limited) comeback on some bikes.
Rim brakes: There are different varieties of rim brakes, including “V-brakes” and “Y-brakes,” but the basic principle is the same. A rim brake uses two pads on either side of the wheel to grab the rim, slowing the rider down. Rim brakes are no longer in favor due to their limited stopping power, difficulty in wet conditions and with rims that aren’t true, and weight considerations.
Disc brakes: Most modern mountain bikes come equipped with disc brakes so for the remainder of this discussion I’ll focus on those.
Hydraulic vs. Mechanical Disc Brakes
There are two flavors of disc brakes on the market: hydraulic (hydros) and mechanical. Hydraulic brakes utilize a piston-cylinder system filled with fluid similar to the brakes you’d find on a motorcycle or car. Mechanical brakes, on the other hand, use a steel cable to translate a pull on the brake lever into a pull on the caliper at the disc.
Hydraulic brakes generally offer more stopping power and many users report improved modulation over mechanical brakes (more on that later).
Mechanical brakes are less expensive and riders will find them easier to maintain and troubleshoot.
Weight differences between hydraulic and mechanical systems are minimal.
The rotor in a disc brake system is the circular disc mounted to the wheel that the brake caliper grabs to slow the bike down. One of the rotor’s main jobs is to dissipate heat caused by braking so manufacturers often use innovative patterns and materials that seek to maximize airflow and heat transfer (while keeping weight low). A rotor’s diameter also dictates heat transfer so gravity-oriented bikes (DH, AM) tend to use larger rotors than cross-country bikes.
Top-end rotors are made in two pieces to both reduce weight and improve heat dissipation. For example, Shimano’s new Ice-Technology rotors feature an aluminum core and a stainless steel braking surface.
To some degree, the position of the caliper mounts on a bike frame dictate the size of the rotor that can be used. The good news is most brake manufacturers include or make available adapters to fit various rotors. After-market rotors are popular with many riders because it’s an easy and inexpensive way to customize a build.
Disc Brake Pads
There are three basic types of disc brake pads for mountain bikes: semi-metallic, sintered, and organic.
Semi-metallic brake pads are known to produce better stopping power and they don’t wear as quickly as organic pads. Out of the box, most brakes will include some type of semi-metallic brake pad.
Sintered pads are also known as metallic pads and are typically used by gravity riders due to their high friction values. In fact, sintered pads generate more friction at higher temperatures than low so they don’t have as much initial bite as organics but work well in extreme conditions.
Organic brake pads (also called resin) offer improved modulation and generate less noise. But remember, they also tend to wear out more quickly and you’ll want to avoid them for wet rides.
Ceramic disc brake pads are also available and in general they’re similar to metallic pads but with improved heat performance.
Brake modulation refers to the way stopping power is affected by the position of the brake lever. For example, a system with high modulation generates a little stopping power for a light pull on the lever, medium power for a medium pull, and so on. A brake system with low (or poor) modulation might instantly jump from low stopping power to full stop with just a minor change in lever pressure. In general disc brake systems offer less modulation than rim-based systems, though they still offer much greater stopping power at the top end.
Mid- to high-end braking systems may feature reach, stroke, and even modulation adjustments. A reach adjustment allows the rider to change the distance from the brake lever to the handlebar, perfect for riders with smaller hands. Stroke adjustment affects the amount of “play” in the brake lever; some riders prefer a long stroke while others prefer a short stroke. Each of these adjustments affects modulation to some degree and in addition to these adjustments, some systems allow the rider to change the ratio of the lever piston to the caliper piston for even greater modulation control.
Choosing an MTB Disc Brake
Armed with an understanding of the basics, it’s time to choose a disc brake system. Manufacturers typically package brake systems based on the type of riding you’ll be doing. Beyond riding style, heavier riders, for example, may want to go with a system with a little extra stopping power even if they intend to stick to mostly XC trails. Look for terms like Trail, DH, FR, and AM to find brakes with more stopping power. You can also look to rotor sizes as an indication of stopping power (remember, larger rotors = more stopping power).
MTB Brake Picks
Want to get a head start on your research? Here are a few recommended disc brake systems to consider.
Formula TheOne: These brakes may be a little pricey but they deliver enormous stopping power in a simple, fairly lightweight package.
Shimano Zee: Bombproof and more affordable than the Saint. You still get Ice Tech and the 4-piston caliper which makes this is a great choice for gravity riders.
Avid XO Trail: The XO Trail brakes feature excellent modulation and very good stopping power. The only downside: these brakes are known to squeal.
Avid XO: Solid brakes in a sexy package with more than enough stopping power for most XC and trail riders.
Shimano XT: Solid, dependable, and reliable. The latest XT brakes feature ceramic pistons and Ice Tech rotors and pads.
Shimano XT M785, SLX M666, Deore M615 Brake Lever Separator Unit
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Formula R1: Formula brakes are built for quality and it shows in the R1 with excellent modulation and minimal fade.
Avid BB7: The only set of mechanical brakes on this list. Still a favorite for their durability and serviceability.
Avid BB7 Cable Boot Kit
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For even more excellent MTB brakes, be sure to check out our list of the best mountain bike brakes as rated by Singletracks members.
Thanks to Syd for contributing to this buyer’s guide.