Most of us are used to the idea of pros using custom frame builders and then sticking the bike sponsor's name on the down tube. Who really thought Jan Ullrich was time trialling on a Giant? And we all loved 7-Eleven's non-Huffy Huffys in the '80s. Gerolsteiner and T-Mobile maybe single-handedly kept Andy Walser living large for the last decade. But it may occur to us less often that when a rider has on a pair of Diadoras, those aren't really Diadoras. Though the brand DMT is a relative newcomer to being visible in the pro peloton, the company has decades of experience manufacturing custom made shoes for some of the top names in the sport. Having long acted as a custom shoe maker means that DMT has an enormous backlog of shoe lasts. This historical data has allowed the designers to incorporate a huge catalogue of foot quirks into their stock shoes.
Enter the DMT Radial -- the top of the line DMT model for riders who eschew mechanical buckles. The Radial 's CX carbon sole is made from Toray MR60, which is a 40 Ton High Modulus Carbon Fiber. That means it has a tensile strength of 40 tons per square cm. In other words, it's got stiffness in spades. Toray is one of the top manufacturers of carbon fiber world-wide -- it's the same stuff used by Pinarello in the Prince Carbon and Montello FP8. The lay-up of the carbon and the shape of the sole are exclusive to DMT.
The soles are made from 9 layers of carbon fiber woven at 0-degree, 45-degree and 90-degree angles. Of course the sole must be looked at as a whole, but each angle in the carbon lay-up will offer strength in different ways. The layers from the inside out are as follows: 0, 45, 45, 90, 0, 45, 0, 0, 45, UD Woven Exterior. Each degree provides different features:
0-degree: Maximum stiffness and responsiveness. This carbon fiber runs the length of the sole providing the stiffness overall for the entire sole.
45-degree: Torsional rigidity allowing an responsive and firm steering feel. It provides stiffness to prevent twisting of the sole due to pronation or supination. During the typical pedal stroke your foot will exert different forces at different vector angles to the sole. Without the torsional rigidity afforded by this layer the sole would be able to twist along its axis leading to a loss of efficiency.
90-degree: Strength and durability for long life and consistent high performance. This layer of carbon fiber helps strengthen the overall form of the sole. Without it the sole wouldn't have the strength to withstand lateral forces. It also helps in increasing the torsional rigidity. The sole functions as a unit but each layer contributes to the overall rigidity of the whole. Without all layers working together the sole would be in danger of twisting slightly, which would rob you of efficiency and power in your pedal stroke.
Another area where these soles excel is in their thickness - or in this case thinness. Keeping the distance between the bottom of the foot and the pedal interface as thin as possible increases the maximum transfer of power to the pedals through more of the stroke. The DMT CX carbon sole uses varying thicknesses in different places. But at the critical cleat interface it is a wispy-thin 3.5 mm allowing for an optimum foot to pedal distance.
The Radial keeps the uppers wonderfully light and fairly traditional with a three strap system. The upper's microfiber combined with the soft mesh guarantees a comfy fit with a maximum amount of circulation. The bonded toe and heel protectors guard against those nasty scuffs that can result from a bit of clopping around the coffee shop parking lot. The Radial weighs 255g in size 41.