When it comes to bicycle brakes, you have two styles to choose from. This guide outlines the pros and cons of disc brakes vs rim brakes to help you decide which to go with for your next bike. I’ll also outline the different types of disc and rim brakes available.
What’s the Difference Between Disc Brakes and Rim Brakes?
Rim brakes stop the bike with brake calipers that apply braking force directly to the flat sides of the bike’s rims. The front caliper mounts to the bikes’ fork and the rear caliper mounts to the seat stays. The calipers have arms that reach down to the rim sides. Brake pads mount on the ends of the caliper arms. When you apply the brakes, the brake pads squeeze against the rim. This creates friction which slows the bike down. Rim brakes are activated with a cable that runs from the brake levers to the calipers.
Disc brakes stop the bike with calipers that apply braking force to rotors (the discs). The rotors mount to the bike’s hubs and spin with the wheels. The calipers mount on the fork and seat or chainstays, near the axles. Brake pads are mounted in the calipers, on either side of the rotor. When you squeeze the brake levers, brake pads push against the rotors to create friction which slows the bike down. These are the same type of brakes that you would find on a motorcycle.
Disc brakes are often actuated by hydraulics rather than cable. When you squeeze the brake levers, hydraulic fluid in the brake lines pressurizes in the system. This pressure causes a piston in the caliper to push the brake pads against the rotor. Some disc brakes are mechanical. These use a cable to activate the caliper just like rim brakes. For more info, check out my guide: hydraulic vs mechanical disc brakes.
Disc Brakes Pros
- Disc brakes offer more stopping power than rim brakes- Disc brakes provide more mechanical advantage than rim brakes. Particularly if they are hydraulic. This allows the calipers to apply more force to the braking surface which helps to slow the bike down faster. Disc brakes also have a larger surface area for the brake pad to grip on to. This increases friction to slow you down faster. Imagine the force it takes to stop 300 pounds of fully loaded touring bike and rider racing down a mountain pass at 40 miles per hour. In this type of situation, you need as much braking power as you can get.
- Heat build-up is less of an issue with disc brakes- When descending a long mountain pass, your brakes generate a lot of heat. If you’re using rim brakes, excessive heat can cause rims, tires, or tubes to fail. The most common problem with too much heat is a tire blowout. Heat increases the air pressure inside of the tire causing the tube to explode or blow your tire off the rim. With disc brakes, your rims stay cool no matter how hard you brake. Disc rotors can overheat as well but they are better at shedding heat than rims because of the thin design. You can ride harder and brake longer without needing to stop and wait for your brakes to cool down.
- Disc brakes perform better in wet weather- When your rim is wet or caked with mud, disc brakes still stop the bike reliably. Water does reduce your braking power slightly but not as much as it does with rim brakes.
- You can ride faster with disc brakes- Because the brakes can stop you faster, you can wait longer before you begin braking. For example, instead of applying the brakes 50 feet before a turn, maybe you can begin braking 20 feet ahead. This saves time.
- Less stress on your hands- Due to the mechanical advantage, you don’t need to put as much pressure on the brake levers when you use disc brakes. This reduces hand fatigue and cramping, particularly on long descents where you’re braking for long periods of time.
- You can ride with bent or untrue wheels- The disc stays the same and will stop you just as well even if your wheels are out of true. This comes in handy if you’re trying to make it to the nearest bike shop after an accident. Rim brakes rub or don’t work as well if your wheel isn’t perfectly true.
- Disc brakes are safer- Because disc brakes provide more stopping power, they reduce your braking distance. This allows you to slow down or stop faster in an emergency situation.
- You can run multiple wheel sizes with disc brakes- If you have one bike that you want to use for road, touring, and mountain use, you can build wheelsets of different rim sizes and simply switch them out with disc brakes. This is great for people who only have the budget or space for one bike. You can mount a set of 700c wheels with slicks for road riding. When you want to go off-road, you can mount your pair of 650b wheels with knobbies.
- Disc brake pads last longer- Because the pads are made of a harder material, they take longer to wear out. This means less frequent maintenance.
- Rims last longer when you use disc brakes- Because disc brakes don’t rub against the rim, the rims don’t get worn down by braking. The rims don’t heat up either. Rim brakes, on the other hand, remove a bit of material from your rims every time you stop. Friction also heats up the rims which causes them to weaken over time. You’ll probably get a few thousand more miles out of your rims when you use disc brakes.
- You don’t have to clean discs as often as rims- Because the discs sit higher off the ground, they don’t collect as much mud or sand as your rims. When using rim brakes, you must clean your rims regularly. If you don’t you risk damaging them if hard contaminants like sand or small rocks get caught in the pad. They can rub against the rim and quickly cause a lot of wear. I learned this the hard way after riding on the beach while touring. I scratched up a rim pretty badly before I got around to cleaning off my pads and rim.
- Disc brakes are more precise- Due to the design, you can better control exactly how much braking force you apply. The wheels are less likely to lock up. This gives you more confidence when riding in hairy conditions. For example, while winter cycling in snowy and icy conditions, you may want to feather your brakes to prevent yourself from losing traction. This is easier with disc brakes.
- You can use wider tires- Disc brakes don’t limit your tire width. The only limit is your frame clearance. When you use rim brakes, your tires must be narrower than the brake arms because the arms must reach around the tire to grip the rim. In some cases, you might have to lower the pressure from your tires so they can clear the brake arms. Wider tires allow more comfort and better traction.
- Disc brakes have a better feel- This applies more to hydraulic disc brakes. For whatever reason, grabbing and pulling the lever just feels more solid and satisfying. Of course, this is a personal preference. High-end rim brakes also feel solid.
- Disc brakes are now allowed in racing- After years of bans, temporary authorizations, and re-bans, the UCI finally authorized the use of disc brakes in road racing.
- Disc brakes are more technologically advanced- Over the past couple of years, professional road racers began using disc brakes. Mountain bikers have been using them for many years. Cycling companies spend a lot of money developing better, safer, and more reliable discs, calipers, and pads to give racers an advantage. This same technology is available to average riders like you and me.
- Disc brakes are the current trend- Almost every high-end bike comes equipped with disc brakes these days. It’s where the industry is going. If you like to have the newest and best equipment, disc brakes are the way to go.
- Look- Many cyclists prefer the way discs look. They are more modern. Of course, this point is entirely subjective.
Disc Brakes Cons
- Disc brakes are more expensive- Because disc brake components are more complex, they cost more. The calipers and pads are more expensive than rim brake calipers and pads. You also need to buy the rotors which aren’t needed on rim brakes because the rim acts as the rotor. Disc brake compatible bike frames also cost more than frames that are designed for rim brakes. The reason is that more braking forces are applied to the non-drive side of a disc brake bike. More engineering is required to design and build the frame. This adds to the cost. If you’re on a tight budget, it’s best to stay away from disc brakes. You can buy a solid used pair for next to nothing and they last forever.
- While touring, disc brake parts are more difficult to find- If you need new pads or replacement parts while touring in the developing world or a remote region, you might have trouble finding them. Small bike shops in developing countries just don’t stock disc pads, rotors, or calipers. You might have ship spare parts in. Most department stores don’t carry disc brake parts either. If the nearest place that sells bike parts is a Walmart, you’re out of luck if you need disc brake pads.
- The wheels can go out of true more easily- Disc brakes put additional strain on the spokes. This happens because the braking force is transmitted through the spokes rather than the rim. Spokes on the disc side of the wheel take the most force. Weak or poorly built wheels can go out of true easily with disc brakes. When this happens, you may experience broken spokes. You may have to true your wheels more often. To solve this issue, you may need to change the spoke pattern so they are offset.
- Disc brakes put stress on the fork legs- Disc brake calipers mount toward the bottom of the fork. When you stop, all of the braking force goes through the thinnest part of the fork, the fork leg. Because of this, you need a more robust fork to safely use disc brakes. Thin forks can fatigue over time and eventually fail. Another problem is that thick disc brake forks don’t absorb shocks as well which makes the ride less comfortable. Rim brakes transmit the braking force through the top of the fork near the stem. This is a much stronger part of the bike. You can get away with a thinner fork that absorbed some shocks and vibration.
- Disc brake pads can rub the rotor- This is a common problem. Because the pads sit just a couple of millimeters away from the rotors, they can easily rub if something is just a tiny bit out of adjustment or the rotor is slightly warped. Listening to the pad rub the disc every revolution gets annoying quickly. Luckily, this generally doesn’t affect performance.
- Disc brakes are a bit harder to maintain and adjust- Disc brakes can be a bit temperamental. You have to keep them adjusted so the pads don’t rub the disc. They need to be adjusted more precisely than rim brakes. If there is a mechanical problem with your disc brakes, it can be harder to diagnose because disc brake calipers are sealed in a housing. You can’t see what’s going on. If you’re using hydraulic disc brakes, you’ll have to bleed the brake lines every year or so and change the brake fluid. This can be a bit tricky if you’ve never done it before. The most common job that you’ll have to do is replacing the pads when they wear out. This job is about the same level of difficulty as changing rim brake pads.
- Disc brakes are heavier than rim brakes- Disc calipers weigh more than rim calipers. You also need rotors, which add more weight unwanted weight to the wheel. If you care about keeping your bike as light as possible, stick to rim brakes. One way you can reduce weight a bit when using disc brakes is to use disc-specific rims. These are thinner and lighter because the rim walls are not used as a braking surface. Even then, the disc brake setup will weigh more.
- Disc brakes are less aerodynamic- The calipers and discs stick out to the side and widen the bike’s profile, creating more wind resistance. The faster you ride, the more important aerodynamics becomes. At speeds over around 10 mph, wind resistance becomes the main force acting against you.
- The disc can cut or burn you- Don’t touch the disc after a long descent. I’ve seen people pour water on their hot discs to see it boil and turn to steam. In the event of a crash, the disc can cut your leg pretty bad. This is part of the reason that road racers have been slow to switch to disc brakes. For more info, check out this article from Bicycling.com explaining how Katie Compton, a cyclocross racer, had her knee sliced open by a disc brake.
- Mechanical disc brakes lack power- Cheap disc brakes may not stop any better than rim brakes. If you’re looking to upgrade, make sure you’re actually gaining performance and not just getting something newer. Hydraulic disc brakes offer the best possible stopping power available on a bicycle.
- Hydraulic disc brakes require additional tools and fluid to maintain- Even though they are incredibly reliable, you don’t want to be stuck in the middle of nowhere after all of your brake fluid leaked out of the brake line. For this reason, most bicycle tourists stay away from hydraulic disc brakes.
- When racing or riding with friends, it can be dangerous to mix disc and rim brake bikes- Some riders complain that differences in stopping and cornering speeds between the two types of brakes make riding together more dangerous. For example, maybe while descending a hill on a rainy day, a disc brake rider slows down quickly. The rim brake rider close behind, can’t slow as quickly and slams into the back of him.
Rim Brake Pros
- Rim brakes are easier to repair and maintain- Rim brakes are simple. If there is a problem, you can tear the whole brake apart on the side of the road with only a multi-tool. It is easier to diagnose a problem with rim brakes as well. Because they are completely open, you can easily see if there is something wrong. Rim brakes are also a lot less touchy than disc brakes. If they aren’t adjusted perfectly, they still work fine. You don’t have to know how to bleed hydraulic brakes.
- Rim brake parts and spares are easy to find anywhere in the world- Rim brakes have been the standard bike brakes for decades. If you’re riding in the developing world, you won’t have any trouble finding calipers, cables, or brake pads wherever you ride. You can find spares in every corner of the world including the smallest village bike shop. If you’re touring in the developed world, you can find replacement pads and cables in most department stores. This is particularly important for bicycle tourists who often find themselves in rural or remote regions where finding spares can be a challenge.
- Rim brakes are cheaper- If you’re on a tight budget, rim brakes are the way to go. Parts and spares cost less because they are simpler and more common. You also don’t need rotors because the rim provides the stopping surface. On average, I would guess that rim brake components cost 10-20% less than comparable disc brake components. Used parts are easily available as well. If you need a caliper, you can buy a used one for just a few dollars at most bike shops. Pads are cheaper as well. For example, I bought a replacement pair for my Schwinn High Sierra for around $1 in Mexico.
- Rim brakes are easier on wheels- Because the brake applies stopping force directly to the rim, it puts much less strain on the spokes. Your wheel stays true longer. You’ll break fewer spokes. For this reason, rim brakes are a better choice if you’re using lower end wheels. Of course, a well-built wheel will stay true regardless of your brake choice.
- Rim brakes are easier on the fork legs- Because rim brakes are mounted high on the fork near the stem, less force is put on the fork legs. This allows for the use of a more flexible fork which provides better shock absorption and comfort. Your fork will last longer without cracking or failing as well.
- High quality rim brakes perform just as well as lower-end disc brakes- If you’re planning to buy a new bike with disc brakes or upgrade your current bike for better braking performance, make sure you’re actually upgrading. Modern rim brakes are very good. Cheap mechanical disc brakes are not that great. In some cases, you may be better off sticking with what you have.
- Rim brakes don’t rub- Because the pads sit further from the braking surface, they don’t rub unless they are poorly adjusted or the wheel is way out of true. If they begin to rub, it’s easy to make a slight adjustment to fix the problem.
- Rim brakes are lighter- If you strive to build the lightest possible bike, you’ll save about 1 pound (450 grams) by using rim brakes. There are no discs and the calipers are smaller, which saves you weight.
- Rim brakes are more aerodynamic- On flat and downhill sections, you gain a slight advantage because you don’t have calipers and rotors sticking out causing drag. The faster your ride, the more important aerodynamics become.
- Rim brakes are safer- Several pro racing cyclists have complained about being cut by the disc during an accident. This isn’t a concern with rim brakes.
- Rim brakes are classic- You probably grew up riding a bike with rim brakes. They have been the standard for decades.
Rim Brake Cons
- Rim brakes don’t have as much stopping power as disc brakes- Rim brakes don’t give you as much mechanical advantage as disc brakes. They have less leverage. We know this because the rim brake pads have to travel further than disc pads for the same amount of brake lever pull. Rim brake pads have to move around a centimeter to touch the rim. Disc pads only have to move a couple of millimeters. This means the calipers can’t apply as much force to the braking surface to slow the bike down. Rim brakes also have a smaller surface area where the pads hit the braking surface. This means they produce less friction. Your stopping distance will be slightly longer when you use rim brakes.
- Rims don’t last as long- Every time you brake with rim brakes, a bit of rim material rubs off. Over the course of thousands of miles of riding, your rims eventually wear out. The friction created by rim brakes rubbing on the rim also heats up the rim. The cycle of heating up the rims with braking and letting them cool off again also weakens the rim over time. The difference isn’t that great but all else being equal, you’ll probably get a few thousand fewer miles out of rims when you use rim brakes.
- Rim brakes don’t work as well in wet weather- When the rims and pads get wet, they get slick. The water reduces friction. This reduces the stopping power of the brakes. Sometimes, your wheel will need to make an entire revolution before the brakes begin to slow you down. During this revolution, the pads squeegee water from the rim. This makes the stopping power inconsistent.
- Heat build-up is an issue with rim brakes- During a long, steep descent, friction causes your rims to heat up. A number of issues can come from this. Most commonly, the heat causes the air pressure in the tire to increase. Usually, the tire will blow off the rim. This is called a blowout. If this happens, you’ll at least need a new tube and maybe a new tire. Worst case, the rim blows out and you need a new wheel. To solve this issue, sometimes you have to stop during a descent and let your rims cool off before continuing to the bottom.
- If your wheel gets bent or too far out of true, you can’t ride- The pad will rub on the rim making riding impossible. This happened to my buddy last year. He took a spill and bent a rim pretty bad. His wheel would hardly spin after because it was rubbing the brake arm. With disc brakes, this wouldn’t have been a problem because the rotor is the stopping surface, no the wheel.
- Rim brakes are more dangerous- Rim brakes generally have a longer stopping distance than disc brakes. If you need to stop quickly in an emergency situation, you may not be able to stop fast enough.
- You can’t easily run multiple wheel sizes- Some riders have one bike that they swap out the wheels for different purposes. For example, maybe they have a 700c wheelset for road riding and a 650b wheelset for mountain biking. You can’t really do this with rim brakes because the rim sits at a different place in relation to the frame. If you want to ride different wheel sizes, you’ll need another bike. Discs always sit in the same location no matter the size of the wheel.
- You have to clean your rims and brake pads often- Sand, mud, or other debris gets stuck on your rim and in the brake pads. When you apply the brake, it scratches up your rims. If you don’t clean the debris off, it can eventually destroy your rims. I learned this the hard way after riding on the beach and not cleaning my rim immediately after.
- Rim brakes aren’t as precise- You can’t control as accurately how much brake you apply. Your wheels are more likely to lock up. This makes riding difficult terrain a bit more challenging because you are more likely to lose traction.
- Using rim brakes isn’t as satisfying- This may be a personal preference or it may have to do with the quality of brakes that I’ve used but rim brakes just don’t feel as solid when I grab the brake lever.
- Rim brake pads don’t last as long- Rim pads use a softer material to improve rim longevity. Because the pads are made of a softer material, they wear out faster.
- Rim brakes can limit your maximum tire width- Rim brake arms have to reach around your tires so they can grip the rim. Some rim brake calipers are too narrow to accommodate wide tires. The tires will rub the brake arms or simply won’t fit between the pads. Disc brakes don’t limit tire width. Your frame and rims are the only limiters.
- Rim brakes are less technologically advanced- After the recent switch from rim brakes to disc brakes in professional cycling, more research and development is going into disc brake technology than ever. The automobile industry has been using disk brakes for years. Some of that technology can be applied to bicycles as well. The result is incredibly smooth, consistent, and reliable braking technology.
- Rim brakes are outdated- The cycling industry is moving away from rim brakes. If you’re in the market for a new bike that you plan to ride for many years, you may want to go with disc brakes to help make your bike more future proof. Who knows, maybe new rim brakes will be hard to find 20 years in the future. Probably not though.
More Cycling Pros and Cons Analyses from Where the Road Forks
- Drop Bars Vs. Flat Bars
- Hardtail Vs. Full Suspension Mountain Bike
- Flat Pedals Vs. Clipless
- 700c Vs. 26 Inch Wheels
- Tube Vs. Tubeless Bicycle Tires
- Internal Gear Hub Vs. Derailleur
- Belt Vs. Chain Drive
- Steel Frame Vs. Aluminum Frame
- Presta Vs. Schrader Valves
Whether you choose to stick with good ol’ rim brakes or upgrade to disc brakes, you have options. Your bike frame and fork determine which type of brakes you can use. Many disc brake bikes include mounting points for rim brakes as well. Most rim brake bikes aren’t compatible with disc brakes because they don’t have the required mounting points for disc rotors and calipers.
Types of Disc Brakes: Mechanical Vs Hydraulic.
Mechanical disc brakes operate with a braided steel cable, just like rim brakes. The system works exactly the same. When you pull the brake lever, the cable pulls a lever on the caliper. This lever squeezes the pads against the rotor to create friction to stop the bike. Mechanical disc brakes use the same pads and rotors as hydraulic disc brakes.
The benefits of mechanical disc brakes are affordability and simplicity. They are also compatible with the same brake levers and integrated shifters as rim brakes.
The main disadvantages of mechanical disc brakes are that they don’t perform as well as hydraulic disc brakes. They don’t provide as much stopping power, they are less sensitive, and you have to pull the brake lever harder to stop the bike. They are also a hassle to keep properly adjusted. If the cable isn’t just right, the pads rub on the disc. Mechanical disc brakes are also heavier than hydraulic.
Hydraulic disc brakes operate with a fluid-filled line. When you squeeze the brake lever, the line pressurizes. This pressure moves a piston in the caliper. The piston pushes the pads against the rotor. This is the same technology used in car and motorcycle disc brakes.
The main benefit of hydraulic disc brakes is performance. They offer strong and consistent stopping power due to the reduced friction in the system. The brakes are also more precise. Another benefit to hydraulic disc brakes is that they require less maintenance once they are set up. They are a closed system that is less likely to be affected by dirt, sand, and other debris. The system is also lighter.
The main drawbacks are the cost, maintenance, and complexity. The system is simply more expensive. The levers, calipers, and brake lines all cost more. Maintenance is also a problem. Even though it’s less frequent, you have to bleed the brake lines periodically because braking performance degrades over time as air bubbles make their way into the fluid in the lines. This job is a bit tricky.
Types of Rim Brakes
Rim brakes come in a number of designs. They all work more or less the same way. The main differences are where the caliper mounts whether it is comprised of one piece or two. A few common types of rim brakes include.
- Caliper Rim Brakes- These brakes attach with a single bolt to the frame and fork directly above the tires. This design allows the arms to center themselves. Caliper brakes perform best on narrow wheels so they are more common on road bikes. Some designs have one pivot point and some have two.
- Cantilever Rim Brakes- These use two separate brake arms that attach to the fork and frame on either side of the wheel. Each arm has its own pivot. One arm attaches directly to the cable and the second attached with a transverse cable that runs between the two arms, usually over the tire. This design doesn’t limit tire width, making them a popular choice for mountain bikes.
- V Brakes (Linear Pull Brakes)- These are basically a redesigned version of cantilever brakes with a side-pull. They mount in the same location on the fork. The main difference is the transverse cable is built into the brake. The caliper consists of just one piece.
- U Brakes- These brakes mount to two points directly on the fork and frame above the rim. They pivot at the mounting point. The arms cross above the wheel and a traverse cable connects the arms. U brakes use the same mounts as roller cam brakes, making them interchangeable. They are common on BMX bikes.
- Hydraulic Rim Brakes- These use fluid-filled lines to operate the caliper, just like hydraulic disc brakes. They offer the same benefits of hydraulic disc brakes including better braking power, precision, and a smooth feel. They also have the same drawbacks.
A Note About Tire Effect on Braking
Your tires play a major role in your bike’s stopping distance. A solid set of disc or rim brakes will be able to lock up your tires if applied hard enough. Low quality or worn-out tires easily lose traction.
When your tires lock up, your brakes aren’t doing anything to stop you. In order to have optimal brake performance, make sure you use quality tires and replace them when the tread wears out.
What Kind of Cyclist Should Choose Disc Brakes?
Disc brakes are ideal for those who plan to ride in poor weather conditions like rain and snow. They also work great in dirty conditions where your rims might get covered with dust, sand, mud, and other debris. Disc brakes provide consistent performance, even when the road or trail gets sloppy. You don’t risk scratching up your rims if they get caked in filth.
Those who ride on mountainous terrain will also be better off with disc brakes. You don’t have to worry about overheating your rim and having a blowout during a long descent. Braking performance doesn’t fade, particularly if you use hydraulic disc brakes.
Riders with a higher budget should also go with disc brakes. If you can afford it, you might as well get the best performance you can get. You’ll feel safer and more confident if you can always stop reliably and consistently.
What Type of Rider Should Choose Rim Brakes?
Rim brakes are ideal for those who only ride recreationally in fair weather. If you just ride on flat bike paths, rim brakes provide more than enough stopping power.
Bicycle tourists and bikepackers who ride in remote regions and developing countries may also find rim brakes preferable due to parts availability. When you’re in the middle of nowhere, it’s easier to find rim brake parts because the technology has been around forever. Used parts are common.
Those on a lower budget should also stick with rim brakes. Components and replacement parts like pads and cables are cheaper.
Final Thoughts: Disc Brakes Vs. Rim Brakes
For most casual riders, rim brakes perform just fine. They’re cheap, reliable, and easy to maintain. Some types of riding require more stopping power or better braking performance. For example, for fully loaded bicycle tourists, the upgrade to disc brakes may be worthwhile. The additional stopping power, less frequent maintenance, and the ability to descent long hills without stopping may come in handy.
In the end, disc brakes vs rim brakes are a bit of a personal preference. Performance-wise, they are similar enough that it’s probably not worth the money to buy a new bike just to get disc brakes. If you’re already in the market for a new bike, discs are worth the additional cost in most cases. The added weight and complexity make up for themselves with the added safety of more powerful braking performance.
Do you prefer disc brakes or rim brakes? Share your thoughts in the comments below!
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