Jerry Moos asked:
"BTW was Ashtabula a separate company, or did it perhaps just refer to a Schwinn manufacturing plant at Ashtabula, OH? As I recall there was a highly-regarded Ford "Ashtabula" (350 ci?) engine manufactured at a Ford plant in that city, so maybe the cranks were a similar story."
ABS (Ashtabula Bow Socket Company...dunno what a bow socket is; possibly OT) was the name of the company that made the bulletproof cranks. They were not part of Schwinn but I am sure counted on Schwinn for the lion-share of sales.
Bay Village, OH USA