Disc brakes have finally established themselves in road cycling and it is only a matter of time before rim brakes will be the exception to the rule. Despite the discussion about safety in competitive road racing having reached its climax this spring, the presence of disc brake equipped road bikes is undeniable in today’s marketplace. Starting from model year 2014 DT Swiss has been offering disc brake specific wheels for road bikes and therefore can rightfully call itself a pioneer. But it was just last season that this niche market really gained momentum and became a trend. Rim designer Andreas Tschanz and product manager Stefan Riehle talk about what’s behind the development process and the challenges disc brakes faced when entering the road cycling world.
PRODUCT MANAGER STEFAN RIEHLE
Only about three years ago road disc brakes were more or less non-existent. There had been first approaches, but the idea was merely present in some product manager’s heads. For about two years now, we see a growing interest, which is mostly triggered by the diversification of the road cycling scene. By introducing new road bike concepts with different fields of application, the consumer now starts to see road bikes as more than just an all out competitive race machine. He learns that road bikes can be much more versatile and still maintain their sporty character. It is of no surprise, that especially the fields of cyclo-cross, endurance and gravel riding perceive disc brake equipped bikes as something worth having. But even in other areas like the Aero segment we see the first models with disc brakes entering the market.
It is a fact that today many new road bike customers have found their way from mountain biking into the road scene. They see their road bikes as a tool for effective training and call out for a brakes as modern and reliable as they know them from their mountain bikes. Not to forget the quickly increasing number of women riding road bikes. Due to their different anatomic preposition, hydraulic disc brakes are tangibly improving their ride experience by requiring less finger force and are becoming a real safety asset.
The percentage of road bikes with disc brakes within our customers’ portfolio has increased tremendously in the last two years. Some customers already start to develop nothing but disc brake road bikes. In numbers: In the model year 2014 we sold about twice the number of rim brake wheels over disc specific wheels. In 2015 the number of disc wheels sold already outweighed the rim brake wheels by 16%.
Rim designer Andreas Tschanz
From a designer’s perspective and a construction point of view, the strict separation of the braking surface and a part responsible for the structural integrity of a bike is highly desirable and brings along major advantages. Both alloy and composite rim brake sidewalls are not suitable to endure high friction situations permanently. A disc brake rotor on the other hand is specifically developed to do just that and does it really well.
Basically disc brakes make things easier when developing a rim, since everything regarding brake performance is handled by a specific part, the brake rotor. The benefit of this is a newly gained freedom to achieve a modern rims main objectives: To either reduce weight or to optimize the ratio between inner rim width and weight. At the same time we naturally strive to maintain the same high level of reliability and quality all DT Swiss products are renowned for. It’s what we have always done and always will keep doing.
Our modern road disc rims come with many of the features that made our MTB rims a benchmark. Key words are a secure bead seat, combined with simple tire mounting and an easy and safe tubeless setup. Furthermore the optimized rim flange geometry results in an impressive ratio of inside width to weight, impact resistance and overall reliability. Given the current speed of technological advancements, I am convinced that we will be able to develop wheels of at least the same weight with major improvements in safety and reliability (I am thinking of overheated composite rims here). And all that will come with vastly improved braking performance. On one hand we can minimize the rotational mass in an important area of the wheel by reducing the rim’s weight, but on the other hand we have to add some extra material in the form of the rotor mounts on the hub and by going up in spoke count.
To me, disc brakes make perfect sense for every kind of rider. They bring along a massive gain in safety and performance. If asked, I will advise every friend of mine to go for disc brakes when buying his next bike. I do see some challenges though when we come to speak about competitive road racing (things like neutral support, interchangeability without dragging rotors, precisely defined hub spacing and axle standards …).But I am convinced those can be solved and that even there disc brakes will take over sooner or later. On a car or a motorbike no one would even consider using rim brakes either, right?