Classic photos of a worn crank sprocket.
One theing that has puzzled me is why the double-row crank sprocket wears more quickly than the single-row. "In theory", the double-row sprocket ought to have half the load on each tooth that a single row sprocket does, so it should wear less. Metallurgy problem?
'73 R60/5 Toaster
Luddite. Not just a philosophy, a way of life...