QUESTION: Are disc brakes really better than rim brakes on a road bike? I’m planning to buy a new bike soon and pretty much every bike has disc brakes in my price category, but I’ve always ridden rim brakes up until now. – Elliot G
RBR’S STAN PURDUM REPLIES: The short answer is yes, but question may soon become academic, at least as far as new bikes go, because the bicycle industry is rapidly abandoning rim brakes in favor of disc brakes on all their new bikes — mountain, gravel, hybrid, road, touring, etc. As you have seen, when buying a new bike, the only choice you’ll likely have is between mechanically operated discs and hydraulically operated discs.
Rim brakes, however, have long been the industry standard and have performed well. They were still in use by at least one powerhouse WorldTour racing team — Ineos Grenadiers — as recently as 2020. They have now made the switch, but while still using rim brakes, they won a lot of races against teams equipped with disc brakes. And, of course, rim brakes will continue to give good service on the many bikes currently equipped with them.
In their favor, however, disc brakes provide increased stopping power, so much more that you often need to apply less force to the brake lever. That can mean less hand fatigue on long descents. Disc brakes also allow greater modulation — the ability to regulate the amount of clamp force on a rotor precisely and accurately — giving you better control while braking.
With rim brakes, each time you apply them, they put a tiny amount of wear on the rim, and some riders have worn their rims so thin that they had to be replaced. Disc brakes avoid wear on the rim. What’s more, disc brakes make it easy to switch to larger width tires, which is prohibited by the distance between the arms of side-pull, center-pull and dual pivot rim brakes, the types found on most road bikes that use rim brakes. (Cantilever rim brakes, found on some touring bikes and tandems, and V-brakes for rims, often used on mountain bikes, can accommodate wider tires.)
Disc brakes can be actuated by either a mechanical or a hydraulic system. Mechanical systems use a braided steel cable, just like the one used with rim brakes, to transfer braking force from the lever to the brake caliper. Hydraulic systems use a sealed fluid line to transfer braking power to the caliper, and they offer the most efficient braking. When they need servicing, however, you may need the help of an experienced bike mechanic who knows how to bleed the hydraulic line. The mechanical systems are less expensive, and you can usually service them yourself.
As long as you want to keep riding your current bike and it has rim brakes, they still work fine and you should! There’s no reason to think that brake pads and other replacement parts for them will not continue to be available.
The next new bike you buy will likely have disc brakes, but in the meantime, enjoy the rim-brakes bike you have.
Stan Purdum has ridden several long-distance bike trips, including an across-America ride recounted in his book Roll Around Heaven All Day, and a trek on U.S. 62, from Niagara Falls, New York, to El Paso, Texas, the subject of his book Playing in Traffic. Stan, a freelance writer and editor, lives in Ohio. See more at www.StanPurdum.com.