The S-Works Crux 5 Frameset is a gravel race frameset for riders building a custom race rig around the lightest possible platform. The FACT 12r carbon frame weighs 789 grams, and the full frameset comes in at 1.63 kg (3 lb, 9.5 oz) in a size 56. Rider First Engineered construction tunes the layup to each frame size for stiffness, where it drives speed, and compliance, where it saves the body. The package includes the matched S-Works FACT carbon fork with a 12x100mm thru-axle and an S-Works Tarmac SL8 carbon seatpost at 15mm offset, with a lightweight saddle clamp and an integrated wedge binder. A 68mm BSA-threaded bottom bracket, 12x142mm rear thru-axle, flat-mount disc interface, and UDH dropout give the builder broad compatibility with SRAM, Shimano, or Campagnolo gravel groups. For the racer specifying every contact point and gram, the Crux 5 frameset is the foundation for a one-off build aimed at the front of the field.