X-LAB RT9 The lightest production road frame ever built. - World's lightest production carbon road frame - A WorldTour-proven climbing bike - Highest performing commercial carbon fiber - Branta C50 ULR 50mm 1230g Carbon Wheelset The RT9 redefines what is possible in lightweight performance engineering.

Constructed from Toray T1100 carbon and refined through extensive structural analysis, the frame weighs an astonishing 550 grams while maintaining the stiffness and durability required for elite racing.

The result is a machine built for the purest expression of climbing performance with instant acceleration, unmatched efficiency, and effortless elevation gain.

The RT9 is the lightest production road bike frame in the world. Period.