S-Works Aethos 2 Break the Rules Weighing only 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 competitive cycling to deliver pure riding pleasure: the Aethos 2 is designed to nearly disappear beneath you, offering incredible agility, smoothness, and sophistication. With increased tire clearance, enhanced components, and data-driven, fit-optimized geometry, even more riders can now enjoy this exceptional riding experience. Aethos 2 defies the rules, all for the love of the ride.