The Cervélo R5 Ultegra Di2 build brings a different character to Cervélo’s pure climbing race bike. Where the Force AXS version emphasizes SRAM’s crisp wireless shifting and compact gearing, the Ultegra build leans on Shimano’s hallmark precision, with a drivetrain rooted in traditional race gearing and the sharp feel of dual-sided power measurement. It gives the bike a classic road racing personality, combined with all the engineering advancements that make the latest R5 lighter, stiffer, and more refined than ever before.

The frame and fork are unchanged, delivering the same ultralight performance as the Force build. At 703 grams for the frame and 329 grams for the fork, the R5 is among the lightest disc-brake race bikes in production. Cervélo has combined this weight savings with significant stiffness gains—21 percent at the head tube and 13 percent at the bottom bracket compared to the previous generation. The result is immediate responsiveness when the rider launches an attack and unflinching confidence when carving through high-speed corners on the descent. Aerodynamic refinements are subtle but meaningful, with a D-shaped down tube and seatpost reducing drag and smoothing airflow around the bottles and rear triangle, while a hidden wedge clamp keeps the seatpost clean in the wind.

The Ultegra Di2 drivetrain sets the tone for this build. Shimano’s R8170 12-speed system brings trickle-down technology from Dura-Ace, maintaining the same precise electronic shifting and ergonomic feel. The crankset runs a 52/36T chainring combination, paired with an 11–30T cassette to deliver a wide gear range that covers fast, flat sprints as well as demanding climbs. The highlight here is the 4iiii Precision Pro dual-sided power meter, providing accurate left and right leg data to give riders the tools for refined training and racing strategies. Shifts are virtually instantaneous under power, with Shimano’s front derailleur in particular standing out for its speed and smoothness—an area where Ultegra retains its long-held reputation.

Braking is handled by Shimano’s Ultegra hydraulic disc system with CL800 rotors. These rotors are engineered with improved heat dissipation for fade-free performance, and the braking feel is light at the lever with smooth, progressive modulation. On technical descents or in dense pack riding, this translates to confident stopping power with intuitive control. It’s a braking system that feels refined, predictable, and consistent across conditions.

The rolling stock mirrors the Force build, with Reserve 34|37 carbon wheels offering asymmetric depths of 34 mm at the front and 37 mm at the rear. This strikes a balance between low weight and aerodynamic efficiency, perfectly suited to the R5’s dual role as both a climber and an all-around race bike. The wheels are built on DT Swiss 240 EXP Ratchet hubs, known for their light weight and reliability, and they’re wrapped in Vittoria Corsa Pro TLR 26 mm tires for low rolling resistance and exceptional grip. The combination is race-ready straight out of the box.

Cervélo’s finishing kit keeps the build sleek and efficient. The HB18 one piece bar stem combo integrate cables cleanly while delivering stiffness and precise control. The Prologo Nago R4 PAS saddle offers ergonomic comfort for long days in the mountains, and the D-shaped seatpost completes the aerodynamic package. Fit and ergonomics match the Force bike, but the Ultegra build carries its own personality, shaped by Shimano’s drivetrain and braking character.

The R5 Ultegra Di2 is more than a spec choice—it’s a different expression of Cervélo’s flagship climbing machine. It feels direct and familiar to riders who prize Shimano’s shifting cadence and braking finesse, with the added benefit of dual-sided power measurement built in. Combined with the ultralight, race-proven R5 frame, it becomes a bike that blends modern engineering with a classic racing feel, precise and measured but every bit as aggressive when the road points up. For riders chasing Grand Tour pedigree with Shimano’s trusted control at their fingertips, this build delivers the ultimate expression of the R5 platform.