Road Disc Bikes
Road disc bikes are becoming much more prevalent in the cycling world and becoming a bit more common in the pro peloton. Road bikes with disc brakes offer riders greater braking power via the discs over rim caliper brakes. There are many braking systems from which to choose and the most powerful is not necessarily the best. It's really important to look at the typical ride the bike is doing and which brake system best fits that situation for each rider who is the one doing the braking.
To ride disc or not to ride disc?
Many riders are connecting with the idea of being able to fit wider tires in their road bikes for the ability to ride with confidence on dirt roads and gravel paths, as well as having greater comfort on broken roads. With disc brakes, tire clearances are determined by the frame - the brakes are no longer a consideration.
As carbon wheels are increasing in popularity, and rim braking on a carbon surface varies in experience for riders depending on weather conditions and the maker of the rims, riders are turning to disc for more certain braking in all conditions and for all lengths of braking times (long, sustained descents).
Hand strength issues and the stronger, easier-to-actuate hydraulic disc brakes can potentially be helpful for those with weak hands, arthritis, nerve damage, or other conditions. The latest generation of hydraulic brifters offered from the big component manufacturers have gotten smaller, so it's easier for those with smaller hands, to be able to shift and reach the brake levers. Prior generations were fairly large and clunky. Alas, we're getting ahead of ourselves. Take a big step back before jumping into assuming you need a disc brake bike.
Disc brakes on road bikes serve a great purpose for people who live and/or ride in mountainous and very hilly areas who have very long, fast descents where constant braking is necessary to stay in control. There is also a significant population who live in wet climates, and people who want to ride regardless of the weather. If the bike is going to be ridden on wet roads, dirty roads, rain or snow, disc brakes are a great option for reliable braking power. Be aware, though, disc brakes are noisy when they're wet!
As the consumer, you have options. Though the big bike manufacturers are cranking out disc brake bikes by the thousands, you should consider first whether or not disc brakes are for you. This decision is a significant one: once you choose disc brakes or not to have disc brakes, your bike can't be modified for the other braking system in the future if you'd like to change brake types. If you get a metal bike, like a Seven, future modifications are an option, though there is a price tag on this kind of wholesale change to a frame. Think deeply about your cycling, your particular braking needs, and make sure we're all on the same page. First, understand why you want disc brakes, then we can hone in on which ones are the best for you.
Servicing Disc Brakes
Disc brakes are not as easy to service as rim caliper brakes. Hydraulic disc brakes are much harder to service than cable-actuated brakes. Internally-routed cables are on yet another order of magnitude of challenge where it comes to servicing them. It's great if you have a good bike shop to lean on - we'll take care of you. However, whether you live near us to have us service your bike or if you would take your bike to a shop closer in proximity, time to service equates to cost to service and the turnaround time.
If you have trouble seeing fine detail, you're going to have problems adjusting your disc brake calipers in relation to the rotor. 1 millimeter versus 2 millimeters between the pad and rotor on each side will make the difference between good braking and not braking soon enough.
The Future Proofing Myth
We've heard quite a few people go through the future-proofing conversation. "I want my bike to have current technology for as long as possible. I see everything going disc, so that's what I should do, right?" If future-proofing is your reason to go with disc brakes, ask anyone who purchased a disc brake bike a couple of years ago if his/her bike is compatible with current disc brake technology. The answer will be "no". That person most likely has post-mount brake calipers and quick release wheels. Current technology is flat-mount calipers and thru-axle wheels. Ask anyone who purchased a rim brake road bike two years ago if his/her bike is current with technology and the answer will be "yes". Ask anyone who purchased a rim brake road bike 10 years ago and the answer will still be "yes", and brake calipers (not tied to the number of speeds of a bike), are still easy to find. Good luck finding the last generation of Shimano hydraulic brifters. Disc brake technology is still evolving and changing. While we can't predict the future of what the big manufacturers will do next, we can guarantee that they will continue to try to change things, and that usually forces obsolescence. Rim brake road bikes settled on a great design years ago, and continues to look the same, and take widely-available parts.
What Problem are you Solving?
Earlier, we mentioned hand strength issues and the benefit of stronger brake power offered by hydraulic brakes. The best question is to ask: have you had problems with rim brakes in the past? If the answer is yes, let's see why. Some road caliper brakes in the past have been "soft" in nature, not offering strong braking performance. Maybe your older equipment isn't the best the market offers now for rim brake calipers. Then again, you might be descending for many minutes at a time and no rim brake will provide you the power you need such that your hands aren't cramping by the end of the long descent. Non-hydraulic brifters are almost always smaller and more ergonomically friendly to small hands.
Disc brake systems weigh more than rim caliper brakes. Disc brake forks weigh more than road caliper forks due to having to be designed to handle torsion at the end of the fork leg. Disc brake frames need to be heavier than rim-brake frames to accommodate for the disc brakes. Disc brake, thru-axle wheels are heavier than their rim-brake counterparts (at the same price and similar durability), and the components that comprise the disc braking system (calipers, rotors, wheels) are heavier than those associated with rim brakes. All of these grams add up to at least a pound and sometimes close to two pounds, depending on systems and frames. The weight impacts performance of the bike.
The cost of hydro or caliper disc brakes, all in, is somewhere around $250-500 more than the rim-brake equivalent between brake system and wheel price differences. As aforementioned, servicing disc brakes is also more expensive throughout the life of the bike.
Hydraulic versus Cable
After reading all of the reasons to go with disc, and you see that disc brakes are for you, now you need to choose between hydraulic and cable-actuated disc brakes. This is a good conversation for us to have in-store, to show you the differences, you can demo ride them and see what you think about the power of one versus the other.
Power of Hydraulic versus Cable Disc
Keep in mind the kind of riding you do while debating this question. If you're a road rider on 25c tires with no hand strength issues, and ride in this area with no significant descents anywhere to be seen, the power of a hydraulic disc brake can be dangerous. The brake can be too strong, forcing the very narrow contact patch between tire and road to lose traction and skid. If you're riding in a paceline and feather the brakes, do you send the rider behind you into you?
Mountain bikes are good examples of bikes and riding that benefit from very power brakes. Hydraulic brakes are very commonly found on mountain bikes. Mixed terrain bikes take advantage of both systems, it's very use-case specific as to whether hydraulic brakes are needed for a mixed terrain rider. Locking up brakes on either mountain or mixed terrain bikes is much less likely due to the bigger tires in use for these kinds of bikes.
Travel and Being Away from Service
Are you thinking you might want to ride this bike across the country, or travel with it on the plane to foreign lands? Just take a moment to imagine what could happen if your hydraulic brake line were to be severed during travel or while you're far from a bike shop. No brake power, no brake in your front or rear. If you get air in the line, same situation. Even if you're a home mechanic, you won't have the proper supplies and tools to do anything about it. Cable-actuated disc brakes are not that challenging and most people can figure out how to do anything that needs to be done on the fly. As with everything, some cable-actuated brakes are great, and many that don't work that well. We will discuss with you with ones your bike should have for the best experience.
Hydraulic brakes: When Everything Works...
...it works really well. Hydraulic disc brakes are great in that they self-adjust as the pads wear and, assuming nothing happens to the hydraulics, they just work. Often, they can go well over a year without needing to be re-bled. Cable-actuated disc brakes need to be adjusted in as the pads wear. This adjustment is simple, but does need to be done. Disc brake pads wear slowly, rarely needing to be changed. It's not hard to change them, but most people feel more comfortable having a mechanic do it.