aerobar gravel bike Cervelo Aspero-5 Gravel Frameset

The Cervelo Aspero-5 Frameset is Cervelo's most aerodynamically developed gravel platform, built from three decades of road and triathlon aero research applied directly to gravel racing. The numbers are specific: 37 watts faster than the previous Áspero at race speed, 34 watts faster than its nearest competitor at the same pace, with the included ST31 carbon stem and HB16 carbon bar contributing nearly 6 of those watts on their own. At $5,500, the frameset ships with the carbon frame, carbon fork, full carbon cockpit, carbon seatpost, aero carbon bottle cages, and a complete integrated downtube storage system — everything needed for a drivetrain-up build.

Aero-Led Carbon Engineering

Cervelo achieved the aerodynamic improvement while also reducing weight. The Áspero-5 frame weighs 1,023g and the fork 393g — 66 grams lighter than the previous generation despite the additional surface area required by the more developed aero profiles. The bottom bracket is T47 threaded BBright: the wide-stance geometry of BBRight in a threaded shell that doesn't require a press and eliminates the long-term creak that affects press-fit interfaces on carbon frames. A UDH (Universal Derailleur Hanger) dropout is standard, keeping the frame compatible with SRAM Transmission drivetrains and forward-compatible as standards evolve. Tire clearance reaches 45mm on 700c, and the geometry is optimized for both matched tire sizing and a mixed-width approach — 40mm front with 44mm rear — a configuration that balances aerodynamic efficiency with handling precision on fast, open terrain. The 422.5mm chainstay stays consistent across all six sizes from 48 to 61cm. Head tube angles run 70.6–72°, stack ranges from 497mm (48cm) to 625mm (61cm), and reach from 369mm to 417mm.

Integrated Downtube Storage

The downtube storage system was adapted from Cervelo's P-Series triathlon platform, where the problem of keeping spares aerodynamically clean has been solved for longer than gravel bikes have existed. A door built into the downtube opens to twin internal storage rolls — one for a flat kit, one for a spare inner tube, each nearly 30cm long — both included with the frameset. The contents stay inside the frame and out of the airflow rather than in jersey pockets or externally mounted bags. The Cervelo front computer/accessory mount 887, rear accessory mount, and Smartpak top tube storage bag 400A also ship with the frameset, completing an accessory ecosystem without requiring third-party sourcing.

Carbon Cockpit and Included Components

The Cervelo ST31 carbon semi-integrated stem and HB16 carbon bar ship with the frameset as the optimized aero cockpit Cervelo engineered the Áspero-5 around. Internal cable routing passes through the stem and into the headset cleanly. The ST31 shares bearing dimensions with Cervelo's R5, Soloist, and Caledonia, so headset and stem components from those models are cross-compatible if you want to reconfigure. Two Arundel Mandible Matte UD carbon bottle cages sit within the Áspero-5's downtube contour, preserving the aero profile of the tubes rather than interrupting it. The Cervelo SP27 carbon seatpost and FSA IS2 tapered headset (1-1/4 lower, 1-1/2 upper) complete the included hardware. What the frameset doesn't include: drivetrain, wheels, brakes, saddle, and pedals — the build elements that let the buyer spec the bike to their standards.

The Áspero-5 debuted under UCI Gravel World Champion Marianne Vos and won. Available in Five Black and Royal Mercury across six sizes from 48 to 61cm, it's a purpose-built gravel race frame for riders who want to build the fastest gravel bike they can around components of their own choosing. Cervelo has done the carbon work, the aero development, and the storage engineering. The rest is up to the builder.