Brakes are one of the most important components of a bicycle: they keep the cyclist safe!
But which brake is better, disc brake or rim brake?
In recent years, the types of brakes best suited for bicycles have been hotly debated among road cyclists, with rim brakes and disc brakes having their own advantages and disadvantages.
So how do disc brakes and rim brakes work? What are the pros and cons of each brake? Not to worry!
In this article, I’ll explain how both brakes work, as well as their pros and cons. Ready for the hotly debated disc brake vs. rim brake showdown?
The biggest difference between disc brake vs. rim brake is that the brake capacity of disc brakes in different weather conditions is more reliable than that of rim brakes, and the replacement cost is low, but the weight of rim brakes is lower than that of disc brakes.
Disc brake vs. rim brake: How disc brake works
Disc brake is one of the newest additions to the world of road cycling in the last decade.
Originally invented by Shimano in 1971 as a development of an industry standard brake, it is interesting to note that disc brakes were originally introduced for road bikes. Shimano is one of the top 10 bike brakes brands in the world.
However, due to the added weight of disc brakes, they were quickly shunned by the road cycling world and never really evolved.
In the late 1980s, as Shimano began to gain a foothold in the MTB world, they looked back at their invention more than a decade earlier and retooled the system for mountain biking, where it has since found a niche.
Since the 1990s, disc brake have been standard on mountain bikes, later adopted by the cross-country cycling community and more recently by gravel bikes.
However, it wasn’t until the 2010s that disc brakes made their long-awaited return to road cycling.
After some hesitation as to whether they should be allowed, they were finally approved by the UCI for use in professional road cycling and have become by far the most common brake in the pro main group.
As a result, disc brakes have at some point been embraced by virtually all cycling programs.
But how do they work? Disc brakes consist of three main components: the caliper, the lever and the rotor.
Essentially, all disc brakes work on the same principle: pulling the lever activates a piston inside the caliper, which grips the rotor, creating friction to slow the wheel.
However, the way these parts are connected differs and the mechanism by which the lever drives the piston. In general, there are two different types of disc brakes: mechanical and hydraulic.
A mechanical disc brake is actuated by a pull cable. This means that the lever and the caliper are connected by a pull cord, which applies tension to the caliper and forces the piston closer to the rotor when the lever is pulled.
The hydraulic disc brake is hydraulically actuated. This means that the lever and the caliper are connected by a “hose” filled with brake fluid.
When the lever is pulled, a small amount of fluid is discharged, forcing the entire fluid column down and exerting force on the piston, which then moves closer to the rotor.
Disc brake vs. rim brake: How rim brake works
It is safe to say that the rim brake has been the standard brake for the road bike industry since the dawn of the road bike industry.
Need no introduction, they can still be found on most road bikes, hybrids and city bikes you’re likely to see on the street.
Rim brakes consist of two main parts: the caliper and the lever. They don’t need a rotor because the pads work on the rim, which is already part of the wheel.
The rim brake works in a similar way to a mechanical disc brake: the lever is attached to the caliper by a cable, and when the lever is pulled, it applies tension to the caliper, forcing the “shingles” to come together and creating friction on the rim.
This creates friction on the rim. Brake shoes are attached to the calipers on either side of the rim, with a small amount of spacing between the shoes and the rim itself.
The two parts are connected by a hinge that allows one to move freely towards the other when tension is applied to the caliper.
Disc brake vs. rim brake: Pros of disc brake
Over the past decade, disc brake vs. rim brake: disc brake have quickly become a favorite of riders, but why?
When comparing the rim brake to the disc brake, usually the biggest advantage offered by the disc brake is its extremely superior braking power.
This is true for both mechanical and hydraulic disc brakes, but hydraulic disc brakes are much more powerful.
In addition, the hydraulic disc brake gives the rider greater control over the braking force through enhanced modulation.
Modulation is the ability to control braking force by squeezing the brake lever to varying degrees.
One of the biggest advantages of disc brake is that their braking ability is more reliable in different weather conditions.
In rain, rim brakes often experience a loss of braking power due to lubrication between the brake pads and the rim.
However, the material of the pads in the disc brake calipers, as well as their better protection against rain, means that they usually do not lose quality during heavy rain.
The brake surface of the pads tends to last longer than the rim brakes because the disc brake is designed to better keep contaminants out.
In addition, replacing just the brake pads is much cheaper than replacing worn rims or wheels.
Disc brake vs. rim brake: Pros of rim brake
Disc brake vs. rim brake: while disc brakes are becoming the preferred choice for many, rim brakes retain many loyal users for a number of reasons.
Perhaps the best reason to stick with rim brake is that the bike is only compatible with them.
If you already have a rim brake and want a disc brake, the frame and fork must be replaced with one that has the correct mounting points for the disc brake calipers.
This is very expensive and will not allow the disc brake to be securely mounted to the rim brake bike.
Also, while rim brakes are more prone to wear, they are a much simpler design than hydraulic disc brakes.
Fixing a rim brake in the event of a failure is usually much easier and less cumbersome than fixing a hydraulic brake.
This simpler design also means there is less that can go wrong. Disc brake owners know how difficult it can be.
The screeching noise or rubbing sound on a disc brake can be very annoying to fix for a variety of reasons, including alignment, contamination, and bent rotors.
Rim brakes, on the other hand, are easier to realign, can be loosened with a lever on the side, and are less likely to have alignment problems to begin with.
Rim brakes may be less effective in rain, but if there are contaminants on the pads or rims, they will not affect long-term performance.
If disc brakes are accidentally contaminated (dirt, degreaser, lubricant) then they will be permanently affected and will require replacement pads and sometimes even rotors. You can also check the best electric dirt bikes for your reference.
Although brake surfaces wear more frequently, it is much easier to check for wear. For the untrained eye, this is a tedious task without removing the disc brake pads, and it is almost impossible to tell if they are worn.
With rim brake, you can tell when rubber pads or rims are worn just by looking at them, even while riding your bike.
Lines on the pads mark the minimum thickness at which they remain effective, and the rims are recessed when they need to be replaced.
The rim brake has another key advantage over the disc brake: weight.
While many in the pro-owner group clearly believe that the performance benefits of disc brakes justify weight loss, it’s a consideration worth keeping in mind for the hillclimbing specialist or lightweight enthusiast.
Considering the weight of the rotors and fluid filled hoses, a disc brake equipped bike can weigh up to 500G more than the equivalent rim brake.
Disc brake vs. rim brake：which is better?
Like most subjective questions like this one, it really depends on your own riding style and discipline.
First of all, if you are a cross-country cyclist who uses dirt, Gravel or mountain bike, then a disc brake is definitely the way to go. What’s the difference between XC bike vs. Gravel bike?
Enhanced modulation, braking power and anti-pollution capabilities make them more suitable for off-road training.
If you ‘re riding a road bike or hybrid bike, the answer is not so black and white.
The first question that should be answered is whether you already have a disc brake vs. rim brake?
Either way, you’ll have to buy a whole new frame and fork to switch to the other-an expensive ordeal. It may not be worth the money to replace the brake system.
For most riders, the benefits of a disc brake, such as modulation, braking power, weather resistance, and lack of contamination, outweigh the benefits of a rim brake (simpler, less cumbersome design).
Then it comes down to budget. Disc brake vs. rim brake: disc brakes tend to only come with mid to high-end kits and above, so these bikes will usually cost more.
Overall, if you have an unlimited budget and are buying a new bike, compare disc brake vs. rim brake: which brake is more powerful and reliable?
All other things being equal, the hydraulic disc brake provides the best braking power, modulation and weather resistance of any brake, which for many will be the most important factor.