I have some Campy Nuovo/Super Record Drivetrains on a couple of my vintage bikes.
I've tried quite a few different chains and freewheels on these Campy drivetrains. Quite a few... They can be set up to shift okay, but they're really fussy. A real PIA, actually. Super Record rear derailleurs are marginally better than the Nuovo Records, but not much. They were designed for close ratio wide spaced freewheels, chain ring differences of about 10 teeth, and wide stiff chains. None of these attributes applies to modern componentry.
Narrow spaced 6 and 7 speed freewheels and flexible bushingless chains are just horrid on these old Campy racing drivetrains: they don't shift accurately when you want them to do so, they're never centered in the gear and you have to fuss around with trimming them, and then by the time they are centered - you'll probably need to shift again... And in the front the chain can "freewheel" between the chainrings at just the moment you need to downshift to put some muscle into the pedals to climb a hill.
The drop parallelogram rear derailleur has a variable chain gap; on the big cog the top pulley is close, on the small cog it's about 2 inches away... You need a relatively stiff chain for this.
The chain ring plateaus on the crankset are wide spaced, and the front derailleur doesn't have a shaped or profiled outer cage plate to push or direct the chain. So you need a chain that will "take a hint" and shift down when it's nudged, and hook up well on the climb. I think that you need flared outer plates for this.
So, after trying dozens of combinations, I've found one that I like. A wide spaced 6 speed 14-26 Suntour freewheel, a Winner Pro would be my preference (eBay, seller ginchm has them frequently) and a SunTour Accushift or DID Superlight chain with flared outer plates (eBay seller countrysideggllc has offered these recently).
For options, I've found that Shimano 6 speed twist tooth freewheels are pretty good too, like the 600 and Dura Ace SIS. And using chainrings cut fro m thinner stock than the Campy originals can help to reduce the distance between the rings and therefore lessen the tendency for the chain to spin between the rings when it doesn't hook up right away.
Other things might work, and I'm sure that someone has something that they think is just fine, but I haven't found anything better than this combination on any of my bikes.
Ed.
> Hello,
> I'm about to setup a Super Record drivetrain on a bike with a 126 rear end
and will be using Suntour (friction) bar-cons.
>
> I'd love to hear some opinions on which freewheel and chain will give me
the best possible shifting combination. I'm open to vintage and new,
whatever works best.
>
> thanks!
> Rod Kronenberg
> Fort Collins, CO
>
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