The Guerciotti of 1982/1983 came with 6 speed blocks, typically a Regina CX 13-21T, though 7 speed freewheels were widely available at the time. HyperGlide wasn't introduced until 1989 but it improves shifting so much that this is one period-incorrect concession that I would readily make.

The maximum cog you can use with the NR derailleur depends on the dropout hanger length and how far back you clamp the axle in the dropout slot. With a Campagnolo 1010/B dropout, the NR derailleur will handle 28T.

HyperGlide came out in 1989. I believe you're thinking of its predecessor, the Uniglide with twisted teeth, that came out in 1978.


He was referring to competition models, which typcially came with 13-21T. The typcial, entry level, sports touring model came with 14-28T.

Avoid Falcon, in my opinion they make the worst freewheels on the market. I've replaced literally dozens for customers. I've seen broken pawl springs, gunked up pawls (they're poorly sealed), split cogs, stripped threads, etc.