(Click for full photo)
1901 - 1910 Sunbeam Newill 3 speed hub Patented 1905.
Shows the r.h. side with changer mechanism and sprocket. Note that the "silent freewheel" is external to the hub and integral with the sprocket - not sure if it would be interchangeable with Sunbeam single-speed freewheels. The fairing on the top of the changer mechanism suggests this is the 1909 model, as in the 1907 version the changer wire is exposed beyond the pulley wheel and the metal sleeve is cylindrical.
Patent no GB190515579
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