Hi all, Regarding the crank on this bike, it looks to me exactly like the standard fare Record arm in 144bcd. I say this because of the "beveling" that runs around the outermost face of the arm, where it meets the sides. The 151 arm that I have (reviewed on this list a few months back, having arrived as a too old part on an all chromed 73 Paramount) has a much more SLIGHT, or shallow beveling than newer versions. This beveling, being smaller, leaves the arm retaining more of a boxed look. My guess is that the arms on this bike were installed later, not unlike the Super Record rear mechanism (although, the chainrings, ring bolts, and dust cap do say "Patent"). I still have photos of a side by side comparison with a 151 and a 144, and will be happy to email them if requested. The shifters are clearly bumpy too.
Best regards,
Mark Agree
Detroit MI