S-Works Aethos 2 Break the Rules Weighing just 595 grams, the S-Works Aethos 2 is the lightest production road bike frame in the world. However, our focus was not solely on weight. We aimed to redefine the rules of cycling by delivering pure riding pleasure: the Aethos 2 is designed to almost disappear beneath you – it is incredibly agile, smooth, and refined. With increased tire clearance, enhanced components, and data-driven, fit-optimized geometry, even more riders can now experience this exceptional ride quality. The Aethos 2 breaks the rules for the love of the ride.