S-Works Aethos 2 Break the Rules Weighing in at only 595 grams, the S-Works Aethos 2 is the lightest mass-produced racing bike frame in the world. However, our focus wasn’t solely on weight. We broke the conventions of racing to deliver pure cycling pleasure: The Aethos 2 is designed to virtually disappear beneath you—it is incredibly agile, smooth, and sophisticated. With increased tire clearance, enhanced components, and a data-driven, fit-optimized geometry, even more riders can now experience this outstanding ride sensation. The Aethos 2 breaks the rules for the love of the ride.