by David Wadsworth
On July 25 Cycling Australia announced that disc brakes will be race legal immediately with the following exceptions: NRS races, elite/U23/U19/para-cycling nationals.
So far in south East Queensland I have yet to see a single disc brake in the racing peloton, but it seems likely that this may change in the near future.
Which prompts the question: SHOULD I GET DISC BRAKES ON MY RACE BIKE?
Examining the pros and cons of any new equipment choice is always worthwhile before spending your hard earned money, as changing to disc brakes entails an entire new frame and wheelsets (hence why the bike manufacturers have been leading the “disc brakes for road bikes” push and not the peloton).
The pros are that braking performance with disc brakes is unquestionably better, especially in the wet, and if you are a mountain biker there is absolutely no doubt you’d choose disc brakes. However remember that cornering performance has more to do with tyre traction on the road rather than how strong the brakes are, so this doesn’t necessarily mean your cornering speed will increase. If you live in a perennially wet climate (like Scotland) then disc brakes will probably be high on your list of priorities. Another albeit minor advantage is replacing a worn brake rotor is easier than replacing the rim when the braking surface wears out, but how often do you actually wear out a rim?
Apart from better stopping power it is pretty hard to find a positive reason for disc brakes on your road bike. If you ask the question “do I currently have enough stopping power when racing” most racers I have spoken to answer “yes”. So is a disc brake really necessary for racing unless the conditions are wet and treacherous?
On the negative side disc brakes require a sturdier (ie heavier) frame and fork, and aerodynamics are compromised. Hang on, aren’t these the two most important marketing pitches manufacturers have been ramming home to us over the past decade? I’ve never heard a racer ask for something on their bike that’ll make them go slower! No doubt in time engineers will work out how to overcome some of these challenges but at the moment your bike will likely become heavier and have more drag.
In a road peloton there is an increased risk of injury with disc brakes since crashes in a bunch often involve multiple riders who fall on each other and onto bikes. The chance of being sliced open by a disc rotor is much higher in a multi-rider incident than say a mountain bike crash where a rider typically falls in isolation and rarely lands on his or her own bike. There is a concern about some riders in the bunch being able to stop faster with disc brakes than those using caliper brakes, so understandably there have been calls for either all riders to use disc brakes or none.
Then there is the issue of a fast wheel change, an essential for racing, but disc wheels are particularly slow to change. Some disc wheels use the standard 6mm quick release axle, and some a thru-axle which is slow to unscrew. Although there are a few thru-axles that have a quick release option these are not widely available (see the offerings from Focus and Colnago for a quick release thru- axle that doesn’t require an allen key). Even if the axle is quick release trying to get the rotor precisely between the narrow gap of the brake pads is VERY slow (manufacturers could make this far quicker by adding quick release lever to spring the brake pads wide apart similar to that found on current caliper brakes). For race spares there needs to be a standard for rotor size, typically 140mm or 160mm on current road bikes. Until a standard is decided neutral spares in a road race will be real problem.
Lastly maintenance presents a greater challenge. Disc brake pads are porous and contaminate easily when washing your bike (detergent and degreaser touching the pads render them next to useless), and the time to change brake pads and bleed hydraulic lines is more than that required for caliper brakes.
Would I get disc brakes to race with? At the moment definitely not on my time trial bike, but I suspect by the start of next season we’ll see a lot more disc brakes on the amateur racing scene and that may lead to a new road bike and wheelsets. Ouch, that’s going to hurt the hip pocket!