Includes shifter, cable, mounting hardware & 25t cog. Bicycle Coaster Brakes Coaster Brakes A coaster brake is a special rear hub for a bicycle, which performs two functions: It allows the bicycle to roll without forcing the pedals to turn. These are the Sturmey Archer S2 Duomatic, and the SRAM Automatix. Mine’s on an old Raleigh Sirocco frame that I’ve built up as a kind of classic roadster.
Probably no good in winter The bearings on the Sturmey Archer S2C are not only unsealed, but practically begging to be contaminated. However the shift point of the hub comes far too early (around 18km/h) and a flat cruising speed puts you at a low cadence that soon feels like a real slog. Hub gears are generally incompatible with quick release mechanisms/skewer axles. It is sometimes possible to select no gear when changing gear, or ‘in gear’ with a poorly adjusted gear cable. In this condition there is complete loss of drive. One of my bikes has one and it’s fantastic to ride. A little back-pedal changes the gear (from high to low, or low to high) and a big back-pedal engages the powerful brake.
The auditory signal is the best pointer to use, as there’s little indication through the drivetrain. After about 700 miles the aluminum hub shell failed but the internals were fine. Rear wheels with drum brakes (a feature on some commuter bicycles) require a reaction arm anyway. One of the most common causes of coaster-brake malfunction is failure to properly secure the reaction arm after removing and re-installing the wheel. If the bike is ridden without the reaction arm properly secured, the arm will rotate downward, effectively loosening the left cone.