Choices in bicycle brakes are usually descibed in terms of rim brakes, cantilever rim brakes, disc brakes, and hydraulic brakes, but within those categories there are better and worse choices for mountain bikes versus road bikes, racing bikes versus touring bikes, and expensive bikes versus affordable bikes This article discusses all of your choices.
Most people who buy a bike don’t pay much attention to the type of brakes it has. I haven’t in the past. If I liked the bike I bought it.
Bicycle brake technology has come a long way over the last 20 years. Bicycle technology is rapidly improving which is also increasing the cost of buying a bike.
Folks who get into cycling, whether road, trail or mountain eventually start learning about all the different bicycle components and start assembling their own bikes buying the best of each for their needs. Brakes included.
As you’ll see below, there are many different bicycle brake options for today’s bikes.
Let’s kick off with the most relevant brakes used on today’s bicycles.
Rim brakes generate braking power by the contact of rubber, leather, or cork pad to the rim of a bicycle wheel, on the inside of the wheel, away from the rubber tire. Rim brakes are activated by pulling a lever mounted on the handlebar.
Rim brakes are still available on less expensive bicycles being built today. They are light. They are inexpensive. They are easy to maintain (although you don’t want to let the pad wear out).
There are a couple of problems with rim brakes. The rims catch water, grease, and grime from the pavement, and rim pads don’t have as much braking power when the rim is wet, greasy, or dirty. Debris like mud, sticks, and road trash can get caught on rims and make brakes totally ineffective. But if you use your bicycle to commute down smoothly paved streets in good weather and you don’t take it off-road, rim brakes can work just fine. Here are three considerations for choosing a bike with rim brakes.
Rim brake maintenance (don’t forget)
If you choose a bike with rim brakes, you need to stick to scheduled maintenance. As brake pads wear down, they may need to be repositioning. The braking motion of rim brakes isn’t perfectly horizontal, so the center of the brake pad may wear out first, decreasing your braking power and your control over how fast you can slow down your bike (or how fast you can’t slow down your bike).
In some situations, the catastrophic failure of rim brakes is a real possibility.
Rim brakes don’t work if rims aren’t straight, so if you damage your rims, you may suffer a catastrophic failure of your rim brakes. Also, you try to carry a heavy load on your bike, or, if you are like me, you are a heavy load on your bike, the braking pad may heat up when you use it. Using your brakes a lot on a long stretch downhill or in heavy traffic with a heavy load can heat up the pads and damage components.
Rim brakes work better when the rims of your bike’s wheels have been treated with a ceramic coating. The ceramic coating also stops the buildup of heat that can damage the brake when you have loaded up your bike.
Be aware of the servo effect.
When you are riding a bicycle with rim brakes, where the brakes are mounted makes a difference. When the front brake is mounted in front of the fork (the connection of the wheel to the frame of your bike), there is a self-assisting or “servo” effect. In this position, the brake generates “leverage” (bending moment) on the bolt where the fork is connected to the frame.
This reduces the amount of force needed to put the brakes on the front wheel, but it would increase the amount of force needed to stop the back wheel. However, both wheels are usually mounted the same way, so you will have more braking power on your front wheel than on the back wheel. The servo effect was what threw my younger brother over the handlebars when he tried to stop at the end of a long hill.
Rim brakes come in a number of subtypes.
Rim brakes are used in different ways in different countries. There are a lot more options than the caliper rim brakes and cantilever rim brakes you will see discussed over and over again.
Bicycles made by Raleigh often have rod-actuated or “rod” brakes. A series of rods and pistons transmit force from the lever on the handlebars to the rim brakes on the wheels. The brake pads are slightly concave rather than flat against the rim. Rod brakes are complicated and hard to repair, but they are also tough and reliable. Those qualities make them a favorite of some Asian- and African-made touring bike companies even today.
Caliper brakes consist of two arms (like a caliper) that extend around the tire from a mount above it. Some models will have dual braking pads but caliper brakes are always mounted at a single point above the tire.
The issue with caliper brakes is that with wider tires, they have less braking power. That’s why they are not used on mountain bikes. But caliper brakes work just fine for most road bikes.
Side-Pull Caliper Brakes
Side-pull caliper brakes have two curved arms meeting at a pivot point above the wheel. They hold the pads on either side of the rim. Each arm has extensions on both sides. One extension is connected to the brake cable and one extension is connected to the cable housing. When you squeeze the brake lever, the arms come together. This causes the two brake pads to generate friction against the rim to stop the wheel.
I have had a personal bad experience with side-pull caliper brakes. The issue with side-pull caliper brakes is that they tend to pull to one side. If you need to slow down fast while you are taking a curve, the stability of your bike may suffer and you may take a fall.
The solution to this problem with single-pivot side-pull caliper brakes is to replace them with dual-pivot side-pull caliper brakes. This makes the brakes less likely to rotate toward one side and less like to cause problems when you are coming to a stop on a curve. The least expensive road bikes still come with single-pivot side-pull caliper brakes, but better road bikes and even some racing bikes now have dual-pivot side-pull caliper brakes.
Cantilever brakes attach each arm of the brake to different pivot points on either side of the fork. The brake shoe is mounted above the rim and is pulled against when the two arms of the brake come together. Cantilever brakes allow for more distance between mounts and pads. This makes them a good brake for “fat” tires on mountain bikes.
The challenge with cantilever brakes is the two arms have to come together precisely to bring pressure on the brake pad. One or both arms can slip so the brake pad slips below the rim and the brake fails. Brake shoes for cantilever brakes are a pain to adjust.
U-brakes are also known as “990-style” brakes after a trademarked sales term. U-brakes have two arm pivots attached directly to the frame or fork of the bike. This distinguishes them from the center-pull caliper brake in which the two arms are attached to the connecting bridge. The pivots are located above the rim. U-brakes are easy to repair and easy to swap out, but they tend to hit the rim higher and higher as they wear out, which can ruin the tire.
The term “V-brake” is actually a trademark owned by bicycle manufacturer Shimano. They are also known as direct-pull brakes or sometimes as linear-pull brakes. They are a side-pull version of cantilever brakes. They are mounted at the same points on the frame, but they have longer arms.
Most of the maintenance issues for V-brakes come from rubbing between the wheels and the brakes. This is most likely to be a problem after you have done flat tire repair or after you put your bike in the trunk of your car.
Roller-Cam Rim Brakes
Roller-cam brakes are popular on BMX bikes. They are like center-pull cantilever brakes, except you stop your bike by pressing a lever that forces the two arms of the brake apart so the brake pad is lifted against the rim of the wheel. Roller-cam brakes are strong and controllable, but they make changing out a wheel a complicated process.
Delta Rim Brakes
A delta brake is a brake with a unique, triangular shape. I won’t go into a lot of details on delta brakes except to say they have the least stopping power of all the kinds of brakes I have reviewed. They are no longer manufactured but you might notice them on an older, used Kronos or Weinmann bike, both of which are rare.
Hydraulic Rim Brakes
Hydraulic rim brakes are used on some e-bikes. What makes a hydraulic rim brake hydraulic is the use of oil pressure rather than mechanical pressure on a wire to operate the brake. Hydraulic rim brakes offer good control at the expense of added weight, but this is not a problem with motor-assisted e-bikes.
Coaster brakes are activated by pedaling backward. They were standard equipment on less-expensive bicycles until the 1980s. When the rider pedals in reverse, a clutch presses the brake mantle. The problem with coaster brakes is they can be activated by slight backward motion not caused by pedaling backward.
My first bike had coaster brakes. There are still a few models of children’s bikes that use them.
A drag brake slows down a bike on a long descent. It’s used when other kinds of brakes could cause a rim to heat enough to blow out. You could still find a bike with this style of brakes made by Japanese manufacturer Arai Helmet, Inc.
Band brakes wrap a cable around a hub to apply pressure against a wheel’s hub to slow it down. Used Yankee brand bikes may have this feature. Band brakes tend to tighten in wet weather, which creates a hazard for bikers on wet roads.
The other major category of brakes of bikes is disc brakes. Disc brakes are attached to the hub of the wheel. Calipers are attached to the frame or fork of the bike with calipers. The calipers push pads against the hub of the wheel to slow it down.
Just about all downhill bikes will have disc brakes. Most mountain bikes have disc brakes. Some racing bikes have disc brakes.
Disc brake design has some distinct advantages over other kinds of brakes for your bike. Hydraulic disc brakes may have a mechanism that adjusts the pistons as the brake pad wears down. This way bikers get the same stopping power from the same amount of force on the braking lever until the pad is completely worn out, although tune-ups may be necessary from time to time.
Buying a bike with disc brakes has some definite advantages.
- Disc brakes fit wide tires.
- Disc brakes dissipate heat better than other kinds of brakes. The larger the disc, the more heat it can carry away from the wheel.
- Disc brakes come with holes in the rotor. This allows water to drain out of the housing.
- Disc brakes perform better in water, mud, ice, and snow. The braking is higher off the ground and less affected by these road hazards. Mountain bikes with disc brakes have fewer problems with mud buildup.
- If your wheel buckles and you have disc brakes, you can keep on biking. This would not be possible with rim brakes because the wheel would get hung up on the brake pads.
- Replacing disc brakes is easier, faster, and cheaper than replacing rim brakes.
- Bikes with disc brakes accept heavier loads.
- Disc brakes are compatible components on bikes that have rear and front suspension.
There are a few disadvantages to disc brakes for your bike:
- You may not be able to add pannier racks to your bike unless you have disc brakes that are designed for them.
- The construction of the disc brake makes the wheel weaker when it undergoes forces pushing to the non-disc side.
- Stopping with disc brakes transfers torque to the bicycle frame. Bicycles have to be made with heavier frames to accommodate disc brakes.
- Repeatedly hitting the brakes hard can cause more damage to the axle with disc brakes than with rim brakes.
Hydraulic disc brakes offer greater control and stopping power than “mechanical” disc brakes. Newer bike models offer hydraulic disc brakes with handlebar controls.
Different kinds of bike brakes offer different amounts of braking power and cause different amounts of wear and tear on your bike. Let’s start with a kind of bike brake you’ll see on only the old-timer bikes.
Old Timer Brakes
Here’s a jaunt through bicycle brake history.
My granddad’s bicycle had spoon brakes. My granddad was born in 1886 and I didn’t come along until about 70 years later. The fact that his bike was still operational 60 or more years after it was built speaks to really, really good maintenance and smart use of the braking system.
Spoon brakes lower a concave piece of metal or leather, shaped like a spoon, directly against the tire to slow it down. Some bikes that use spoon brakes have a right-side hand lever for operating the brake. This was common when I was growing up in the 1950s and 1960s. In developing countries today, many bikes have spoon brakes, because they are easy to make in a tool shop, but they are operated by pedaling backward.
Spoon brakes press directly against the tire, so they increase tire wear. However, if you keep changing out tires, your brakes will last indefinitely. But you aren’t likely to find spoon brakes on a bike outside of the developing world or my garage.
Duck brakes were the latest thing in bicycle components in 1897. A duck brake consists of two rollers that drop down against the front tire when the rider pulls a long lever. The lever multiplies the force the rider uses to stop the bike and having tool rollers instead of one spoon ensures better contact with the tire. Duck brakes are an improvement over spoon brakes for controlled deceleration. They are a lot easier to use when biking on slick pavement. But you won’t find them on any but antique road bicycles today.