Reddit mentions of Forte Single-Speed Conversion Kit

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This kit easily converts most freehub gear systems into a single speed systemGoing single speed saves on weight, simplifies your drivetrain, increases efficiency and makes your bike a heck of a lot easier to maintainSmooth and quiet operationIncludes a Forte chain tensioner, eight spacers of 4.5mm width and three spacers of 3mm width (spacers fit Shimano compatible freehub bodies)Also includes three cogs: 16, 18 and 20 tooth, Shimano compatible cassette lockring and detailed instructions