Editor's Note: Freewheeling is the ongoing column of features editor Jason Sumner. Once a week (usually), he'll use this space to prattle on about all things cycling, be them interesting, innovative, inane or annoying. If you have a comment or question, or just want to sound off, drop a note in the comments section below.

Unless you've been living at Ted Kaczynski's old place up in the Montana backcountry, you've surely heard the news by now: The road disc brake revolution is underway.

Starting in earnest at last August's EuroBike trade show, when disc-equipped road bikes were ubiquitous, the cycling industry looks to be steadily embracing this braking technology that's been commonplace on mountain bikes for years. As of this writing, Specialized, BMC, Parlee, Colnago, Salsa, Volagi and Time were just some of the bike manufacturers currently offering road frames that can accommodate disc brakes. Add cyclocross bikes to that equation, and the number grows exponentially.

Then last month came confirmation of one of the worst kept secrets in the two-wheeled industry: Chicago-based SRAM released a pair of new hydraulic braking systems, one for rim brakes (Hydro Road Rim), the other for disc (Hydro Road Disc).

We got the chance to test out SRAM's new hydraulic disc option during a 90-minute test ride at the Sea Otter Classic (Here's the Strava file.) Needless to say, we were duly impressed. Despite our best attempts to overheat the brakes by braking hard while pedaling fast downhill, power and modulation remained strong, steady and consistent.

Perhaps more impressive, though, was how little hand effort was required. I was easily able to quickly decelerate from 35mph to 10mph using minimal force with just one finger on each lever. It was akin to the one-finger braking mountain bikers have loved and relied on for years.

Here's SRAM PR man Michael Zellmann talking more about our test ride, the new braking systems, and SRAM's new 11-speed Red and Force drivetrains, which SRAM calls "22" in reference to the fact that cross chaining is possible, allowing the use of all 22 gear options. (We tested this, too, and encountered no problems or chain rub even when going big ring to big cog or little ring to little cog.) You can also see an expansive gallery of the new groupsets on page 4 of this article.


SRAM's big news, coupled with the fact that Shimano will almost certainly follow suit with a hydraulic disc brake option sometime this summer, will likely spell the slow demise of mechanical disc brakes on road bikes (good riddance), and speed up adoption of this new braking option.

That's not to say traditional rim brakes are headed the way of the dodo bird. But it's hard to envision a near-future scenario where disc-equipped road bikes are not occupying at least some of the prominent space on bike shop floors around the country.

"As a company, we are not coming out with anything right away, but think back to when disc brakes first came on the scene in mountain biking," Scott Bikes PR man Adrian Montgomery told me at Sea Otter. "Right away people were going faster with disc brakes because they could brake later and with more consistency. The same thing could certainly be true for road biking. And in my personal opinion, I think the UCI legalizing disc brakes would really be in the best interest of the riders. I think a lot of the crashes you see on high speed descents may be due to rims heating up the glue on tubulars and having them roll off."

Montgomery's "safety" angle is perhaps the best argument for road disc. By moving the braking interface away from the rim, you free riders from many of the associated concerns of overheated brakes - primarily when those riders are running carbon wheels in the rain.

Instead of worrying about a hot spot on your carbon rim causing your inner tube to explode, or stressing about wet roads rendering your rim brakes useless, you can relish the fact that heat dissipation at the rim is no longer an issue, and that disc brakes work well wet or dry. And because disc brake rotors are smaller in diameter than wheel rims, disc-brake pads need to squeeze with roughly 1,000 pounds of force before lock-up occurs. Conversely traditional rim brakes need only about 200 pounds of applied force before skidding commences.

This wider "braking window" equates to better braking modulation and more control of braking force. Anyone who's ridden a disc-brake equipped mountain bike with 180mm or 200mm rotors understands the confidence boost that comes from knowing you can bomb a downhill, but still quickly scrub speed in a safe and controlled manner.

"I rode some of SRAM's disc stuff throughout last year's cyclocross season," explained multi-time U.S. national champ Tim Johnson. "Part of that time was riding hydraulic and it worked great. Going into corners you could brake later, which meant an overall increase in speed. But a lot of people are still skeptical, wondering why they'd need it. Well when you ride it you realize that you don't just use brakes to lock them up. If you can brake safer, it's going to improve the quality of your ride."

Of course Johnson's slant is decidedly 'cross focused, where the impact of things like added weight and reduced aerodynamics are less profound. We don't have full weights of the new SRAM system, but it's reasonable to expect that swapping on disc brakes could add anywhere from 200 to 500 grams of heft to your rig. This number remains in flux in part because the industry is still trying to nail down what size disc rotors will work for the various applications, be them 'cross, gravel road riding, or going full monty, and dive bombing steep paved mountain roads at 55mph.

This is ample ammunition for some disc detractors, who remain unconvinced that change is for the good. "I think when people discover how much heavier [disc brake systems] are, and how much they detract from the aesthetic of what we have come to envision as the ideal form of a road bike, that is going to be tough for a lot of people," said Mavic PR man Zack Vestal, alluding to the fact that a pair of 160mm rotors can easily weigh 160 grams. "I honestly think it is going to be more niche for more years than everybody is willing to admit at this point."

Out of the gate, SRAM is recommending 160mm rotors for paved use and 140mm for off road. But others within the industry see those numbers as a still-moving target.

"Of course like everyone else, we are looking at disc and seeing where we should go with it," said Cervélo founder and chairman Phil White. "The feedback so far is that you can't do 140mm disc rotors, it has to be 160mm or maybe even 180mm. And that becomes a challenge for aerodynamics and weight. But certainly we are looking at road disc, we just but don't have an informed position yet."

It should be noted that White - and just about anyone who builds time trial bikes -- is a fan of hydraulic rim brakes. Cervélo's recently released its revamped P3 time trial bike, which is spec'd with Magura's RT6 hydraulic rim brakes. The advantage, of course, is that hydraulic systems don't encounter the same routing issues as cable-actuated brakes when it comes to navigating the circuitous shapes of TT bike frames. They also typically have a more aero shape, tucking inside the borders of frame tubing better than their cable-actuated cousins.

"Obviously disc brakes require some special modifications to frames, but hydraulic rim brakes can be mounted to anything," said Charles Becker, SRAM's category manger for road and triathlon. "With Hydro Rim Road you get a ton of the benefits that come with hydraulic braking even though it's still a pad on a rim. The amount of hand effort required is much less, and you are totally freed from cable routing issues because hydraulic hoses don't care what shape they are in. So a lot of these aero bikes with the very challenging routing issues can now easily be overcome, whereas a bad angle with a cable system can really effect the performance of the brake."

Becker's first statement, that disc brakes require some frame modifications, leads one to wonder how deeply the industry has already committed to this new technology. You would assume that the SRAM brain trust wouldn't release new technology into a marketplace that's not ready to accept it. And indeed, it appears that's the case.

"We have been working with several bike manufacturers for two-plus years on this project," SRAM's Becker confirmed. "There are already many bikes that are ready [for disc brakes]. The bikes you see here [at the SRAM Red 22 launch at Sea Otter] are production Specialized Roubaix bikes. And of course cyclocross disc frames have been around for a while now. Most are mechanical, but they can certainly be converted to hydraulic."

More importantly, said Becker, was the fact that the hydraulic disc project was in part a collaborative effort. "We have been sharing specifications [with some bike makers] the whole way. I wouldn't call it total co-development. But certainly we've been keeping each other abreast on the products that are being designed to make sure they are compatible. We also share data back and forth because we need the bike makers to do the proper testing. And we've had them build us frames so we could take [the hydraulic systems] out on the roads and test them ourselves."

Even after all that development time and testing, Becker calls SRAM's first go at hydraulic braking "conservative."

"We didn't shoot for making the lightest possible system," he said. "We wanted it to be super robust and we wanted it to fit a multitude of frames without having to create special standards. But I think as things evolve, you'll see people figuring out how the different forces affect things. You'll see changes on where the brakes are attached. There will be quite a bit of learning over the next few years as everyone figures out how to use these new technologies."

So someday could we see a Tour de France winner crossing the finish line on the Champs-Élysées aboard a disc-equipped bike? "Someday, maybe," guessed Becker. "But a lot will have to come together in terms of frames, wheels, race support. It will all need to homogeneous across the peloton. And that is something that is out of our control. What I can tell you is that no one in the industry makes money making bikes for UCI racing. That just costs us money."

Like nearly all new products that come onto the cycling market, the UCI is currently giving disc brakes the proverbial sniff test. But Becker says there are no deadlines or even time lines on when that process might conclude. "We are in the business of making products that are useful to the consumer," he added. "Hopefully we can convince the powers that be, but we are selling the product regardless."

There's much irony in Becker's final statement. Normally top pros get first crack at new cycling technology, and then it trickles down to consumers. But this time, you and I will get the chance to ride road disc long before Alberto Contador or Bradley Wiggins get clearance to race it.

So what will we do with this newfound access to disc brakes? And do we really need them? Many will argue the answer is, no. In an on-going RoadBikeReview poll, nearly 50 percent of respondents answered, "Don't need them," when asked what their stance on road disc was. Another 32 percent labeled themselves, "Interested, but waiting another year."

I personally fall into the third category, which represented 8 percent of the poll respondents, who answered they wanted a set of hydraulic disc brakes sooner rather than later. To my way of thinking the new possibilities simply outweigh the negatives.

Scott Bikes' Montgomery agrees. "It would open up so much more terrain for riding if I had brakes that worked better," he said. "For instance, I like to ride my 'cross bike on mellow single track trails sometimes. And if I had better brakes I could actually get some swoopy trail turns in. But because I am trying to keep my speed in check using 1990s technology, I cant."

Even if aggressive cyclocross riding isn't your thing, it's likely at least some who are reading this enjoy the occasional road bike foray onto dirt roads. There again you have a situation where better, more modulated braking could be a huge performance advantage. Think about dropping down a wash-boarded section of gravel road, or bending around a loose dirt, sharp turn. Indeed, disc brakes -- and the opportunity to run wider tires because you are not limited by caliper width -- could turn our road bikes into true Swiss Army knives, capable of conquering all types of terrain.

It's also worth noting that what some will call an ungainly tall brake lever hood (SRAM claims its 1cm taller than standard models) to me simply represents one more secure place to grab hold of. And what's wrong with that?

As for questions of weight and aerodynamics, there aren't any really good answers yet. Yes your bike will be a little heavier, and no it wont be as aero. But I personally am not overly concerned with being ultra aero, and I honestly believe that within a few product cycles, the industry will come up with creative - and safe - ways to keep the weight penalty in check. In the meantime, I'll make up lost time on the descents. Let the revolution roll on.