Updated: Jun 7, 2022
Whether you're a performance cyclist or a hobbyist just starting out, you undoubtedly already understand the importance of your bike's braking system. But what's the best type of brakes to use? Disc brakes or rim brakes? It's a question that has aroused a raging debate in cycling-related discussion boards and forums.
Chris Froome, for example, is one of the high-profile pros who has publicly stated that he's not all in on the new brake system yet, especially on the pro peloton circuit. He even said, as recently as February 2021, that disc brakes are "still a work in progress."
But of course, there are two sides to every debate. Disc brakes have their proponents too, with many pro athletes throwing their support behind them. The men's pro teams in the recently concluded Paris Roubaix, for example, have long adopted disc brakes with the last holdout, Team Sky/Ineos, recently joining the fray with the Pinarello Dogma F.
So, what's the big difference between rim and disc brakes?
Rim brakes have been around the longest and use pads that grip the wheel rims to slow down or stop the bike. These brake pads can wear down over time, particularly if you ride in wet or muddy conditions, and must be replaced periodically. Rim brakes are also less powerful than disc brakes, which can be an issue if you're trying to stop quickly.
Cyclist using a bike equipped with rim brakes on a descent in clear conditions.
On the other hand, Disc brakes use pads that grip a spinning disk (or rotor) to slow down or stop the bike. They are typically more powerful than rim brakes and work significantly better in wet weather, making them a popular choice among cyclists who like training during the rainy season. However, disc brakes have some disadvantages too, like the additional weight and aerodynamic penalty that might not appeal to many cyclists.
A bike equipped with disc brakes in motion.
So which type of brake is right for you? Ultimately, the decision will depend on your individual preferences and riding style. But with this overview of the pros and cons of both disc and rim brakes, you should be able to make an informed decision about which type is best suited to your needs.
Benefits: Is it really the future of cycling?
Most bike manufacturers seem to be slowly shifting their attention to disc brakes, with more framesets and groupsets being crafted to accommodate the new braking technology.
Superior Stopping Power
One of the main advantages of a disc brake system is its stopping power. It allows cyclists to slam their brakes later into a turn giving it a slight advantage in terms of cornering. Its braking power is also a considerable advantage when cyclists need to avoid sudden crashes.
There are many reasons for sudden braking in a peloton, such as a crash up in front. Or reasons to feather the brakes.
Higher Degree of Modulation
Speaking of stopping power, the pressure needed to apply on the brake lever should also be significantly less on a disc brake as the pads are notably closer to the rotor. Because of this, riders have, far and away, a greater level of modulation on disc than on rim brakes. This means that the level of pressure on the brake lever is accurately translated onto the rotors giving riders more control over their braking.
Hands fully gripping the brake levers while riding in the drops.
Wet and snowy weather conditions make rim brakes unsafe, as moisture on the brake line serves as a lubricant that can significantly reduce friction and overall braking power. The wide clearance between the brake pads and the brake line can also get leaves, grit, and dust stuck in between, which can affect its performance. This problem is effectively eliminated by disc brakes as the holes on the rotors drain the moisture, and the small clearance between brake pads and rotors makes it nearly impossible.
A light drizzle amidst city traffic.
Service Life and Longevity
Disc brakes also give a more bike service life and longevity. Because friction is the main force behind the stopping power, the braking surface and the brake pads naturally wear out over time. With rim brakes, cyclists often have to replace the entire wheelset once the rims have worn out. This cycle can be costly, especially if you want to use carbon fiber wheelsets. On the other hand, disc brakes need only the rotors changed once worn out, keeping your precious carbon wheelset safe and pristine for much longer. So, if you're the type of rider who can really run up the mileage, you're definitely going to want to use disc brakes.
This bike is getting a white glove treatment, or just adjusting the rear derailleur.
Disadvantages: Should I stay with my rim brakes?
While there are many advantages to using disc brakes for performance cycling, some drawbacks should be considered. And for a lot of riders, some of these factors are enough to make them stay with their rim brake-kitted bike.
The Dreaded Disc Rub
One of the most common complaints about disc brakes is that they can be extremely finicky and complicated. The pad clearance, for example, makes slight alignment issues cause disc rub, which Chris Froome has made abundantly clear that he's not a fan of.
Weight and Aerodynamic Penalties
On the performance side of things, disc brakes can also be disadvantageous in certain conditions. Disc brake systems can weigh up to 500g more than rim brake gruppos. This could translate into a lot of additional power required to move the bike forward, especially on routes with a lot of ascents. Furthermore, there's an aerodynamic penalty for the additional components on a disc brake. An experiment by GCN shows that the disc brake version of a bike can cause a 4W-16W penalty compared to the rim brake configuration of the same bike. Unfortunately, these factors can significantly impact your ride quality and overall satisfaction with your bike. It can even make or break your experience with a disc brake-equipped bike.
Significantly More Expensive
Disc brakes tend to be more expensive than rim brakes, both initially and in terms of replacement parts over time. Bike components that can accommodate disc brakes, such as framesets and wheelsets, for example, are generally more expensive than those that are meant for rim brakes.
The instantly recognizable dura ace disc rotor costs around $100 USD each.
Factors to Consider When Choosing Between Disc or Rim Brakes
When deciding between disc and rim brakes for your performance cycling needs, there are several factors you should consider. These include:
How often do you ride in wet or muddy conditions? This can affect the wear and effectiveness of your brake pads over time.
Your budget, considering that disc brakes designed for road bikes tends to cost a lot, especially if you want to make your bike as light as possible.
Your own personal preferences, as some riders simply prefer the feel or responsiveness of one type of brake over the other.
Some riders, such as those using team-sponsored equipment, may not even get a choice.
Whether you are a competitive racer or simply enjoy cycling as a hobby, choosing the right braking system can have a big impact on your riding experience. While rim brakes have traditionally been the standard choice for performance cyclists, recent advances in disc brake technology have made this type a more attractive option for many riders.
Overall, there are several advantages to using disc brakes over rim brakes for performance cycling. They tend to be more powerful and effective, work better in wet weather conditions, and require less maintenance than rim brakes over time. However, they are also typically more expensive and may not be compatible with specific bike setups or wheel types. Not to mention that there are several issues that have recently come up regarding the relatively new braking system's reliability.
When choosing between these two options, it is essential to consider factors such as your budget, riding conditions, and individual preferences. Whether you decide to go with disc or rim brakes, make sure to do your research and find the best option for your needs!