Today I want to discus disc brakes on Bicycles. I want to stay away from simple discussions with categories of bikes where disc brakes are already generally accepted and move on to see what the future holds for this technology.
This year manufacturers have made a large push to incorporate disc brakes into the cyclocross scene. This move has been accepted in many different ways. Many people are totally against it saying it is unnecessary to have disc brakes on a cyclocross bike because they provide an unnecessary amount of braking power for a bike that traditionally hasn’t had or needed much braking power. Many people also argue it is heavier to have disc brakes on a cyclocross bike, and one that I hear a lot is that my carbon wheels won’t be able to be used on both my road bike and my cross bike or my old cross bike and my new cross bike. I would like to take a deeper look into disc brakes on cross bikes and give my general position on them.
I will start off by saying that last year during cyclocross season the thought of disc brakes on a cyclocross bike made me laugh, literally. I saw them an unnecessary amount of braking on a bike that wasn’t made to handle extremely rough terrain. Even though I wasn’t yet an advocate for disc brakes I hated cantilevers with a passion. I had never had good luck with them and had tried three different makes of them. I turned to trying short pull V-brakes. The short pull V-brakes did supply additional braking power but the thing I found with them was that it was on or off. I was either braking very slow, or I was skidding my tires. My basic thought after this was if I’m running a 32mm wide tire and I lock up my brakes one of two things will happen they will slow down over the course of 15 feet or so with poor braking or I would lock them up and skid for 15 feet, this meant to me that the cantilever issue wasn’t really solved with the V-brakes. I saw the issue as a matter of braking power to traction. This is the same reason I would say that a disc brake hasn’t been seen as very useful on a road bike, with a 23mm slick how fast can you slow it down a skid is a skid.
This season many manufacturers have produced disc options for cross bikes in their line or even a full line of only disc cross bikes. Working on the retail end of the industry this movement has inspired me to try it. After all I assume the industry leaders in frames know more about bicycle performance then I would. So I moved to a new bike with mechanical disc brakes. After purchasing this bike I was frantically trying to find a company that I could purchase a pair of real cross wheels from for the bike. By real cross wheels I mean a medium depth carbon rim with a tubular tire surface, but I needed a disk hub. I could not find any wheels just yet because no major manufacturer has created these wheels yet. I have seen people build up wheels for a situation like this but I didn’t want to build a pair of wheels because then they would have a braking surface and when real carbon disc cross wheels come out I would have invested a lot of money and time in a pair of wheels that were “chop shopped” together when the technology wasn’t yet there.
So after my hunt for wheels my first cross race of the season came and I entered it running my stock clincher disc hub wheels with some nice grippy clincher tires. Last year I wouldn’t have been caught dead on a non tubular wheel for cyclocross racing. When racing I found a few things very shocking. First of all I didn’t find that I was missing much traction from the tubular wheels being absent once the brakes were more predictable. What I mean by this is that the reason I found I needed the tubular tires was so that I would have more traction through the turns when my brakes would not feather as well. I found that with the disc brakes I was using my brakes a lot more but not as aggressively as I would use my cantilevers or my V-brakes. I was able to slow into turns much more predictably and pedal through turns a lot faster than a traditional cross setup. In fact I found that I was taking turns a lot faster than most of my competitors who were on cantilevers, and trust me I’m not the fastest on the cross course. I also found the brakes saved me a lot of energy because while I was cruising through turns much smoother my competitors would have to sprint after a turn for a few pedal strokes to stay on my wheel. If I decided to sprint out of a turn I could almost certainly drop the person behind me a few more seconds back. The other thing I found with the disc brakes is that I was able to take more risks when moving slowly through obstacles. If I was turning and moving slow I could be real easy on the brakes or not even use them because if I was going to make a mistake I could brake a lot faster than a cantilever is able to. This meant I could compensate for minor judgment errors due to my braking and take riskier lines yet avoid time loosing mistakes.
Now I told this story to a fellow cross racer at the 2012 Interbike trade show this year and he found it wasn’t the same. He told me that he saw very little difference in running disc as oppose to cantilevers. I found this strange and then he explained why. He was racing cross in an area where it was mostly harder packed ground; he felt that the traction wasn’t a very big difference to his racing style. Secondly he found that the courses he raced on were very limited in the number of turns they use so there wasn’t much of an advantage to be cooking it through the turns but rather time was made up being fast in the straighter less technical sections. Myself on the contrary I race in Illinois, we have very rich loose soil, traction is very important. Also The Chicago Cross Cup tends to be in more urban and suburban parks meaning the parks are small and making a 1-2 mile course requires a lot of turns in a smaller space so cornering is very important to having a good race.
So now we get to the discussion, are they unnecessary? Are the completely necessary? Or is it situational? In my mind I would say necessary just because of what I have seen firsthand. I would say if you were a professional cyclocross racer and you had to travel and were given many different soil types and cross courses you better have a bike that can handle a loose rugged twisty course as well as a smooth hard packed fast course. This is where I say you can’t have a bike that is too advanced but you can have a bike that’s not advanced enough. My general opinion is that it’s a generally better braking system in not for the braking power as much as the modulation of the brakes. Being able to feather the brakes with more control made me feel more in control of the bike and I would say the weight difference is incredibly minimal due to the amount of benefit it serves.
I see many cyclists against technology such as this just because they say it’s more then anyone needs on a cyclocross bike. When I hear a response like this all I can see is that the person is comparing disc brakes on mountain bikes to disc brakes on cross bikes. Where in mountain bikes they are necessary and accepted as necessary, on the cyclocross end they give an advantage and should be considered superior for other reasons. If we look at cross country mountain biking it is not a whole lot different from cyclocross as far as the reasons for having good brakes. For downhill and free ride mountain biking braking obviously is important for the control and safety aspect more than anything but in cross county mountain biking the main advantage to a disc brake isn’t how fast you can come to a stop but rather how well you can slow into and pedal out of turns. As they say you can only go as fast as your brakes allow you to slow down. Very similar to why you would want good brakes in cyclocross. After all there was a time when disc brakes didn’t exist in cross country mountain biking and look at the difference they have made in that aspect of racing.
If there is a competitive advantage and another rider has it while you don’t it is not too much for that type of racing, it is almost necessary. In fact there was once a time when road racers were against STI shifting because it was slightly heavier then down tube shifter, that all changed when people started shifting more often on road bikes and all the down tube bikes couldn’t keep up having to shift less in a race. Can you imagine where cycling would be if STI shifting never caught on? At the end of the day a cyclist need to try all products and weight the advantages to disadvantages with an open mind before making judgment. In my mind it was plain to see that the weight advantage to cantilever brakes didn’t mean anything compared to the difference in performace of the bike with disc brakes.
So what is the future of disc brakes on bikes? Will it stay in cyclocross? What about road? In fact this year Colnago decided to launch their C59 frame with hydraulic disc brakes on it. Is this technology important in road? What about time trials? Well it’s hard to say because it hasn’t really been done much but here is what I can say on the subject. Any further advancement in cycling with disc brakes is going to depend solely on the manufacturers. For instance some have already caught on to it. TRP now makes the Parabox, a device mounted under the stem that allows a bike to convert a mechanical lever to a hydraulic master cylinder with a hydraulic line and brake. One step further Formula brakes has created the first STI hydraulic road lever. It’s a baby step into the game as it only works with Shimano DI2 and Campagnolo EPS systems but it is a step. Let’s say disc brakes are put on all drop bar bicycles, what could this mean for carbon wheels? If wheel manufactures can eliminate the need to have a heavy duty braking surface that is stiff and wears slowly perhaps the rotating mass of a wheel will go down drastically and we will see more performance out for wheels. Or the rim shape isn’t restricted by a braking surface, such as aero rim designs from zipp which have tried rounder shapes and wider shapes but have been restricted by the need for a braking surface. Maybe for time trials we wouldn’t have to fuss with aero linear pull brakes but rather we could hide a disk behind the fork much more discretely. Whatever the future holds for disc brakes on bicycles it all comes down to the main three manufacturers, if either Shimano, Sram or Capagnolo back one of these systems it might gain some ground. But until then it’s hard to say what performance it might enhance on a bicycle or what the drawbacks could be. Who knows maybe disc brakes could be the next STI shifter or clipless pedal where you wouldn’t race a bike without it?
Chris Enockson, Store Manager Bicycle Heaven