The Ratio Mech is a modular, user-serviceable derailleur designed from the ground-up here in the Lake District, UK. Optimized for 1x drivetrains, the Mech can be used with a wide range of cassette and shifter pairings. Due to the wide range of mounting options and cassette pairings we’ve created some explainer guides to help you decide on your set-up.

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Compatibility

The Mech allows you to get what you want from your drivetrain. You want to run a Shimano GRX shifter with a Shimano 10-51T cassette but also want to use your UDH dropout? You’d like to run 13 speed but have SRAM 11 speed road shifters? No problem.

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Direct mount versus hanger mount

Direct mount offers great advantages over traditional hanger mount. More robust and less prone to shifting issues, we wanted to create a product that would allow for a greater range of cassettes to be compatible with SRAM UDH dropouts.

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B-Gap setting

The Mech is designed for an easy set-up process. Etched graphics give you an easy way to check your B-Gap and ensure the best shifting possible. Each cassette and shifter combination needs a slightly different set-up.

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