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Wm. H. Fauber or GWM La Porte Indiana, (besides Iver Johnson and perhaps others) may have used the slotted drive pin(?); but also undersized crank shafts.
The first picture shows a tape measure and what looks like (to some eyeballs), less than a 15/16” hole in the chain ring sprocket(?).
Perhaps a more precise measurement might be helpful(?).