245 metres in altitude, an average gradient of 13 percent - these are the parameters for the TOUR disc brake test, in which the new Dura-Ace disc was meticulously tested. TOUR editor Manuel Jekel bravely plunged down the mountain.
We were eagerly awaiting the test because the old Ice-Tech disc with a diameter of 160 millimetres had surprisingly failed in our tests: 245 metres of climbing with an average gradient of a good 13 percent were too much at the time - the aluminium core between the stainless steel pads became soft and the brake failed. Do the new, large air deflectors cool the new disc better?
Once the brakes have been applied, they manage our reference descent in top speed mode with hard, precise braking. It is easy and sensitive to modulate, does not squeal and also copes with the final full braking from 61 km/h to a standstill - the disc remains intact. The new cooling design works. Then we complete a hesitant descent with continuous braking and stay below 50 km/h, as is often typical for anxious, insecure racing cyclists. The bends can be mastered with ease, but the simulated emergency stop at the end also overloads the new system. The front brake fails temporarily, but does not break. Full braking power is available again after a short cool-down. For objective classification, it should be noted that many carbon rims with rim brakes delaminate and are destroyed during such braking; and in the case of aluminium rims, tube bursts due to overheating are a frequently observed consequence of such braking behaviour.
Our test verdict on the Dura-Ace disc brake
The new design is an improvement. For fast and light riders, the new Dura-Ace disc is great and a clear recommendation. But heavy riders who tackle extreme descents can also push the new system to its limits. As our test shows, we recommend a system weight of 100 kilograms as the upper limit.
