New gravel bike Specialized Crux 5: 789 gram race bike frame and aero advantage

Specialized developed the Crux 5 according to the "Time to Finish" method, which combines aerodynamics, weight, rolling resistance and route profile in a simulation for a calculated ride time to the finish. The Unbound Gravel course over 320 kilometres served as a benchmark. According to the manufacturer, the calculations show a time saving of 9:58 minutes compared to the Crux 4 under identical conditions. Among other things, the simulation takes into account the surface roughness, which was recorded using telemetry sensors during races such as Unbound 2025.

Frame and weight

Low weight remained an important development goal; the predecessor Crux 4 was one of the lightest gravel bikes on the market. The S-Works frame of the top model made from so-called FACT 12r carbon is said to weigh just 789 grams. Even with the aerodynamic Roval Terra Aero CLX III wheels, the top model is said to weigh in at 7.1 kg. A new addition to the line-up is a quality level called S-Level, which is positioned between the top-of-the-range S-Works version and the mid-range Expert model. The S-Level model with FACT 10r carbon weighs 897 grams as a frame, fully assembled with top components in the form of a SRAM Red AXS drivetrain and Roval Aero wheels, it weighs 7.7 kilograms.

Aerodynamics and wind tunnel

The aerodynamics were developed in a wind tunnel using a dummy with moving legs; the test simulates the air flow on a moving cyclist. Specialized claims to have achieved 15.2 watts less air resistance at 45 km/h with the Crux 5 compared to the Crux 4. The aero gain is split 50 per cent between the frame, fork and seatpost, with the Roval Terra Aero wheels contributing 30 per cent. The new integrated Terra cockpit contributes a further 20 per cent. The tube shapes are visibly based on the Tarmac SL8 competition road racer; Specialized built prototypes with a combination of Crux 4 and Tarmac SL8 parts.

Geometry and tyre clearance

The Crux 5 now offers space for 55 millimetre wide tyres, i.e. up to 2.2-inch mountain bike format. The geometry has been adapted to the requirements of modern gravel racing formats: The steering angle is 0.5 degrees slacker, the seat angle 0.5 degrees steeper and the bottom bracket height lower. With this trick, the Crux should now be more stable on rough surfaces, especially at high speeds, but also less playful on tricky terrain. This means that the geometry is finally moving away from the cyclocross bike as which the Crux was once introduced and the last Crux 4 was still to be used. This is accompanied by a larger turning circle and more sluggish steering behaviour in tight bends as well as lower ground clearance, which is now a disadvantage for classic cross-country riding. The riding position, on the other hand, has only been adjusted slightly. The reach increases moderately depending on the size, by a few millimetres from 397 to 400 mm for size 56. The steeper seat angle means that you sit slightly further forward on the Crux 5. Specialised states that the stiffness and comfort values correspond to the Crux 4.

Models and prices

The top-of-the-range S-Works Crux 5 AXS version costs € 13,999. It uses the lightweight FACT 12r frame and fork, Terra Aero CLX wheels with carbon spokes, ceramic bearings from CeramicSpeed and an S-Works Power saddle. There are no alternatives to the SRAM RED AXS XPLR 1x13 drivetrain in the top class.

The Crux 5 S-Level with FACT 10r frame, FACT 12r fork and SRAM RED AXS XPLR costs € 10,499. At first glance, it appears to be equipped identically to the top-of-the-range S-Works model, but the wheels come with steel spokes and cheaper DT Swiss hubs, and the ceramic bearings in the wheels, headset and bottom bracket are not included in the package.

The Expert model with SRAM Force AXS XPLR is priced at 6,999 euros, with SRAM Rival XPLR costs the Comp model 4,499 euros. The only version equipped with Shimano gears is the entry-level Sport model for 3,999 euros. In Germany, only the S-Works version is available as a frameset for 5,799 euros.