At 5:01 PM -0700 7/26/07, Kurt Sperry wrote:
>Actually I've discovered a Nuovo will shift beautifully and effrtlessly even
>across a new 14-28 Shimano twist tooth FW. I guess I'm just not critical
>enough about shifting performance, that's the only explanation I can fathom
>why people seem to not like shifting vintage Campagnolo.
The problem exists mostly with very small cogs - 13 or 12 teeth. The Nuovo Record derailleur swings away from the freewheel as it goes to smaller cogs - at the same time as the cogs get smaller - so you dramatically increase the chain gap on the small cogs.
For years, I and many others thought our return springs had lost their spring, and thus were a bit reluctant to move the derailleur that last bit. The real problem is that the upper derailleur pulley is so far from the cog that the chain just bends, rather than derail onto the next cog.
If you try to use the NR with a flexible 7-speed chain and a 12-21 freewheel, you will find it hard to get onto those last two cogs (13 and 12). On the other hand, your 14-28 freewheel should shift just fine with a Nuovo Record or even an old Gran Sport derailleur... (However, the Gran Sport wouldn't be able to handle much of a difference in front chainrings.)
When I raced, I've spent a few downhills praying the derailleur finally would go into the 12-tooth cog as people wound it up toward the finish line. Not having Ergo wasn't a problem - I still used a Super Record in Category 2 racing in 1999 - but in retrospect, I probably should have replaced my 7-speed freewheel with a 6-speed and used a wider, stiffer chain...
On the other hand, on the uphills, I never missed a shift or had any other disadvantage due to my "obsolete, poorly shifting" derailleurs. In sprints, I usually selected the final gear before getting out of the saddle, and then it was just a question of getting the rpm (and power output) high enough to get ahead of the other guys. Being more of a climber, I rarely won a sprint, but as I got better at sprinting, even the competition's switching to Ergo/STI didn't seem to make a difference. The guys who beat me with downtube shifters continued to beat me when they got Ergo. The guys who didn't quite make it past me with downtube shifters fared no better once they got a new bike with Ergo/STI.
By the way, the on-the-road shifting performance of a large variety of classic derailleurs was tested and described in two Bicycle Quarterly articles in Vol. 4, Nos. 2 and 4.
Jan Heine
Editor
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