S-Works Aethos 2 Break the Rules Weighing just 595 grams, the S-Works Aethos 2 is the lightest mass-produced racing bike frame in the world. However, that wasn't our main focus. We aimed to break the rules of cycling by delivering pure joy on the road: the Aethos 2 is designed to virtually 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 outstanding ride quality. The Aethos 2 defies the rules, driven by a passion for riding.