SRAM

Red Exogram GXP Crankset

The first generation Red crankset used a foam core with a carbon structure wrapped around it to meet SRAM's ambitions for drivetrain performance and weight. While the stiff crank arms offered excellent response under load, one complaint that came from a handful of ProTour riders was that under load the front shifts sometimes lacked sufficient precision and crispness. SRAM's team of R&D experts set out to solve this gripe and the changes you'll find on the Red Exogram GXP Crankset directly correlate to improved shifting.

The new SRAM Red Exogram GXP Crankset has gone away from that original foam-core formula, and now has a significantly beefier arm shape with a true hollow cross section. Because of its larger carbon-optimizing structure, SRAM is able to use less material, effectively reducing weight without negatively affecting stiffness. This also allowed them to rotate the spider to take advantage of the large, flex-fighting crank arm.

SRAM chose to stick with the 130mm bolt circle diameter standard, ensuring compatibility with aftermarket chainrings, but they've arranged the spider to position a mounting bolt on the backside of the crank arm. By integrating a mounting location within the existing carbon structure, they're able to reduce weight and deflection from shifting -- effectively enhancing the accuracy, speed, and quality of front shifts. This reduces the number of spider arms to four and gives the cranks a sleek, air-splitting profile.

The Red Exogram chainrings have also received extensive reworking to boost front shifting performance, specifically focusing on integration with the rotating, Yaw-caged Red front derailleur. Coined X Glide R, these chainrings are machined from 5mm thick 7075-T6 aluminum, but this machining isn't of the Swiss-cheese, punch-holes-everywhere variety. SRAM used extensive computer-aided finite element analysis to optimize stiffness first, followed by shift ramp profiles. Then they set out to eliminate any unnecessary material without affecting the structure. SRAM placed the new shift pins to correlate with your cadence and cut the ramps to into a profile that works seamlessly with the new Red front derailleur.

The Red Exogram GXP Crankset does not come with a bottom bracket, but is compatible with the SRAM/Truvativ GXP standard, including the low-friction hybrid ceramic bearing option. It comes in 170, 172.5, and 175mm lengths, and both 53/39 and 50/34 chainring configurations are available.