They’re still making headlines for the wrong reasons in professional road racing but thousands of recreational riders already use disc brakes on road-going rides. Why isn’t this already a done deal?
The roadies among us can’t help to be aware of the ongoing debate about whether disc brakes should or should not be allowed in the professional peloton. The UCI (cycling’s international governing body) are currently trialing disc brakes, meaning the likes of Froome, Cavendish and co can choose them over traditional calipers. However – and it’s a big however – several ‘incidents’ have left riders questioning their safety, the latest involving Team Sky’s Owain Doull and a sliced shoe at February’s Abu Dhabi, purportedly caused by a crash and contact with German sprinter Marcel Kittel’s disc rotors.
Whether the rotating rotor element of a disc brake ruined Doull’s shoes – or a high-speed scrape up against a metal barrier as some observers believe – remains inconclusive. What’s more clear is that they’ve split professional opinion.
A high-speed pack of pro’s using a mixture or disc and caliper brakes – and thus having different amounts of stopping power at their immediate disposal – as we currently see, might be asking for trouble. While detractors question they’re dangerous in a peloton of 100 riders who are all either using discs or calipers, the likes of Kittel recognise their many benefits, ‘I think they’re a good choice for this weather condition [rain],’ the big German told the press before this week’s Paris-Nice. ‘I’ve said before that I believe in disc brakes. I’m convinced.’
Amateurs ahead of pro’s
Many thousands of recreational road cyclists around the world are also convinced, unusually for new cycling gear rolling onto the market, disc brakes have appeared on amateur bikes before the pros; in fact, the majority of sportives around the globe let us “completers, not competers” use disc brakes. They’ve also been used in mountain biking and cyclocross for years. But why? What are the advantages over the tried-and-trusted calipers? Good question…
‘Give it a few years and cantilevers will be a thing of the past,’ says disc convert and 2011 British cyclocross champion Paul Oldham. ‘There are numerous benefits of disc brakes. You can brake far later into corners. Your braking surface isn’t ruined when the roads are grimy. They stop more reliably…’
Oldham’s clearly a fan but what are the physical differences between a rim brake and disc version that stimulates these numerous benefits? The main one is where the braking power is applied. While rim brakes clamp directly onto the wheel rim, discs transfer braking duties to a separate rotor – the one that’s causing that indifference in the professional ranks – that’s mounted to the wheel’s hub. It’s similar to what you’d find on a car or motorbike. The brake caliper continues to be mounted to the frame and fork but is placed much closer to the wheel axle.
Disc brakes are commonly the hydraulic variety. This means traditional brake cables and housing are replaced by a non-compressible fluid and a hose in a fully sealed system. When you pull on your brake lever, it pushes a plunger in a master cylinder. In turn, this pushes that fluid through a hose to the caliper at the other end. This pressure pushes pistons on the caliper and clamps pads onto the rotor, and, in turn, provides better modulation of braking and greater reliability. But the strongest argument is their performance in the wet. They’re simply more consistent than calipers, especially when using rim brakes on carbon rims, which are notoriously indifferent when the rains pour.
Don’t turn back
The majority of riders who’ve used disc brakes on their road machines never turn back. They inspire greater confidence, meaning once fearsome descents are tackled with speed and style. In fact, for some of the pros, their performance is deemed too good, their superior stopping power a concern in a packed peloton descending at 50mph. These packed pelotons simply aren’t a concern for your everyday rider.
So will discs soon be the only brake in the peloton or will calipers remain? Clearly there are issues to iron out, with that rotating disc a concern for some, but time and technology will inevitably solve any perceived issues. The industry’s also keen for discs to become omnipresent on the road, as without having to cater for calipers, wheel and frame manufacturers will be given (relative) freedom to tear up the design rulebook. Cue higher-volume tyres and wider rims for improved traction, and more aerodynamic wheels. While the compact disc may be dying, disc brakes on road bikes are set for an exciting, popular and long life.
And for the rest of us… well we have options. There are many bikes you’ll see at the Spin Cycling Festival that come disc-equipped, there are many more that use calipers, and a whole host that come with options.
As with any new technology, it’s best to make an informed choice. Come and chat to the many exhibitors who’ll give you the benefit of their experience, and for some, let you find out for yourself on our test track.