Originally Posted by
Jeff Wills
A 1973 bike would have a 2 chainring x 5 cog drivetrain with a 1/2” x 3/32” derailleur chain. Any chain made for 5-6-7-8-speed bikes will work.
Since it only skips on one cog, was that cog inspected for wear?
Agreed, wrong chain is probably not the culprit. When you say 10th gear, do you mean easiest or hardest gear? If hardest, it’s likely your smallest freewheel cog is worn, or rear derailleur high limit needs a slight adjustment.