Rear Hub Inspection

I dropped from the lower bracket of the drainpipe onto the courtyard gravel. Leaning against the rough brickwork stood an old bicycle. I climbed onto the rear axle hub to inspect the gear cassette. Nine stamped steel sprockets nested along the spindle, gripped by an oiled roller chain. Below them hung a spring-loaded derailleur arm. Bracing my boots against the frame dropout, I pushed the lower pulley cage forward with one palm. The arm pivoted against its internal coil, tightening the chain until the resistance peaked. I eased my grip, letting the mechanism snap back into precise alignment. Reliable construction.