An innovative and ultra-light carbon chainring designed, developed and manufactured in Barcelona for MTB, gravel and road bikes. The Gemini Rigel combines a forged carbon body with a hardened aluminum tooth core for a drivetrain that is lighter, stiffer, and quieter than anything conventional construction delivers.
Gemini is a Barcelona-based composites studio that designs and manufactures carbon components entirely in-house. The Rigel is their most technically ambitious piece: a carbon chainring built around a manufacturing process so unconventional it has generated two international patent applications. More than 500 prototypes and three years of development separate the idea from the finished product.
The Rigel combines a forged carbon body with a 7075-T6 aluminum core at each tooth. The aluminum handles chain contact and wear resistance. The carbon wraps around it laterally, reducing dynamic friction and noise with every link. The result is a drivetrain that runs measurably smoother and quieter than conventional chainrings, at a weight no aluminum or standard carbon construction can match. The lightest version of the Rigel, in the SRAM 3-bolt configuration, comes in at around 39g.
What sets it apart
The key is the Continuous Fiber Teeth process. Using over 100 tons of controlled pressure, Gemini arranges the composite fibers concentrically around the metal core inside the mold. This structural organisation is impossible to achieve with layered carbon or CNC-machined blanks, and it is what gives the Rigel its stiffness-to-weight ratio. Every chainring is handcrafted at the Gemini workshop in Barcelona.
The Rigel is available across MTB, gravel and road builds. Interface options cover the full spectrum of modern cranksets, making it a genuine drop-in upgrade regardless of discipline or drivetrain brand.
Specifications
Material
Forged carbon body, 7075-T6 aluminum tooth core
Disciplines
MTB, Gravel, Road
Sizes
32T, 34T, 36T (MTB) and road/gravel sizing available
