Why don't cyclo-cross bicycles have full chain guards like this? (They would of course be shaped with the derailleur gearing kept in mind.) You can make these guards from plastic and their
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derailleur - Installing a chainguard on a bike with derauiller - Bicycles Stack Exchange
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Bikes For The Rest Of Us: The Elusive Chain Guard
Chain Guards - TRAC DYNAMICS
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Is a chain guard useful? » MHW Bike Magazine
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