Disc brakes have been commonplace in mountain biking and cyclocross for years, but now, thanks to some rejigged rules by the UCI (cycling's global governing body), we're also going to be seeing them used more and more in professional road racing. And whatever happens in the the pro peloton, you can guarantee it's going to get copied by commercial cycling brands. There are lots of benefits to disc brakes, regardless of what type of riding you do – here's five of them.
Compared to traditional rim (AKA cantilever) brakes, the stopping power of discs is far superior. Technically speaking, rim brakes work by squeezing soft rubber pads against a compressible brake track (the two sides of the rim). With discs, a stiff calliper squeezes large incompressible pads against an incompressible stainless steel rotor, or 'disc'. The mechanism can feel twitchy and grabby at first because of the improved precision, but once you get used to the improved braking, you'll enjoy the sensation of riding with far greater control.
2. Efficiency in all weather conditions
This is the biggest selling point for the average cyclist. There is some concern among professional riders that on steep and long Pyrenean and Alpine descents the discs could reach unsafe temperatures, but for you average Tom, Dick and Bradley riding in the UK – where variable conditions are inevitable – the all-weather capabilities of discs outweigh all the disadvantages.
Whereas the brake surface on rims is basically road-level (and in the puddles), discs are located at the centre of the wheel so are far less affected by water, grit and any contaminants that might lie on the road. Consequently, the braking efficiency varies considerably less than with rims brakes.
3. Wheel maintenance
The nature of squeezing brake pads against the rim walls means that there is a high risk of wear, particularly if you continue to ride through the winter months and on lumpier terrain where you will brake more frequently. Disc brakes void this risk entirely, taking all the pressure away from the rims.
With traditional brakes the wheel needs to be perfectly true to avoid rubbing against the pads, a massive faff to get right. With discs you need to make sure that the rotor and callipers are aligned, but there is less pressure to get the wheel rolling perfectly straight. So you can wave goodbye to the sinking feeling that comes with needing to find someone who knows what they’re doing when it comes to truing wheels after hitting that concealed pothole!
4. Carbon rims
Pairing rim brakes with carbon rims has always carried an element of risk; there is not an even distribution of friction and heat on the brake surface which can lead to problems with the integrity of the material on long descents. A big issue with carbon rims comes in wet conditions where grip is lost almost completely. Introduce carbon rims to disc brakes and suddenly you have all the benefits of precise braking and the lightweight, aero qualities of carbon rolled into one!
5. The pros are doing it!
Reliable sources predict that the pro peloton will all be riding discs by 2018, so if the pros are all for it, it’s a no-brainer, right?
Granted, there are teething problems with the technology at the moment, not least because Campagnolo, sponsor of some of the biggest teams in the peloton (Astana, Movistar…) has still not arrived at the party. The CEO said that testing had commenced in 2013, but no evidence of so much as a prototype is yet to surface.
The biggest concern among riders and mechanics is the rate at which a wheel can be replaced during a race as there is no quick release and there could be issues with properly aligning the callipers to the rotor.
However, testing this season has been positive and now that the UCI is onboard with the idea, after some more testing and development to iron out the few issues that remain, the outcome is inevitable. And let’s be honest, we all take motivation and inspiration from the riders on the pro circuit.
Gone are the days of clenched jaw, white-knuckled squeezing of the levers when descending with traditional rim brakes. For greater control and peace of mind, discs are the future.
Do as the pros do. Embrace the disc!