Only the smoothest stuff. The Cannondale SuperSix EVO officially clears 32 mm tires (some reviewers have squeezed 34 mm in, but Cannondale's spec is 32). That's enough for chip-seal, hard-pack rail trails, and the occasional dirt road shortcut.

For anything chunkier — washboard, loose gravel, true gravel races — the Cannondale SuperX is the right tool. Different category, different bike.

Both bikes share a 555 mm stack at size 54, and both run an aggressive race position. Cannondale built the SuperX explicitly so a SuperSix EVO rider can hop across without rethinking their fit.

The differences are in the dirt-specific bits: the SuperX's chainstays grow from 410 to 422 mm, the wheelbase stretches by about 10 mm at size 54, the head angle slackens to 71 degrees, and the fork offset extends to 55 mm. All of it adds up to more stability when the surface gets loose, without changing where your hands and saddle sit.

The Cannondale SuperSix EVO, by a meaningful margin. Cannondale claims a 12-watt aero saving at 45 km/h vs. the previous generation, and the LAB71 build hits the UCI 6.9 kg weight limit in a 56. The SuperSix is also running 28 mm slick tubeless road tires from the factory on most builds, vs. the SuperX's 40 mm Vittoria Terreno T50 knobbies.

If you put gravel rubber on the EVO and slick tires on the SuperX, the EVO still wins — lower weight, deeper aero road wheels, and faster road geometry.

The Cannondale SuperX. The 48 mm tire clearance lets you run actual gravel rubber at race pressures, the longer wheelbase keeps the bike planted on washboard descents, and the rear-end compliance (flex zones plus the D-shaped seatpost) cuts the fatigue that grinds you down in a five-hour race effort.

The SuperSix EVO maxes out at 32 mm and has no compliance features built into the chassis — it's not designed for sustained off-pavement work.

Cannondale SuperSix EVO: 32 mm officially. Some reviewers have fit 34 mm with tight clearance at the chainstays — Cannondale's spec is 32.

Cannondale SuperX: 48 mm at the rear, 51 mm at the fork. Granfondo confirmed plenty of room around 45 mm tires in their 2025 test. That's enough for almost any gravel race tire on the market.

Both are vastly easier to live with than the previous generations. Both moved to a threaded BSA bottom bracket (no more PF30A creak), both use the Delta steerer with standard headset bearings (no proprietary parts), and both eliminated the steering-stop pin that caused warranty issues on the Gen 3 EVO.

The Di2 battery moved from the seatpost to a downtube port on the EVO, which most reviewers prefer — a couple noted concerns about water ingress at the new location, so wipe the area down after wet rides.

The SystemBar R-One on the higher builds of both bikes is a one-piece full-carbon integrated cockpit — adjusting bar width or stem length means buying a new unit. Hose bleeds require partial disassembly, roughly an hour at a shop.

If you'd rather keep things adjustable, the lower-tier builds on both bikes ship with the Cannondale C1 Conceal alloy stem and a separate bar, which lets you swap either component without re-routing hoses. That's how the EVO 1 ($9,499) and SuperX 2 ($7,499) come specced.

On the road side, the SuperSix EVO 3 at $6,999 (105 Di2) is the value play — same frame, same handling, electronic shifting at the lowest electronic-shifting price point in the lineup. Step up to the EVO 2 ($6,499 — Ultegra Di2 and HollowGram carbon wheels) if you want carbon hoops at a similar price.

On the gravel side, the SuperX 1 at $7,499 (Force XPLR AXS, SystemBar R-One, DT Swiss GRC 1400 carbon wheels) is the sweet spot — full integrated cockpit and carbon wheels without paying the LAB71 premium.