You guys were more up to date than we were. Gitane Tours de France and Peugeot PX-10s came with 52-40 Stronglights, and Raleigh Pros and Internationals came with 52-45 NRs, and we all replaced the small rings with a 49 or 48. Normandy hubs on the Peugeots, Tipo on the Gitanes, and Record on the Raleighs. Sedis chains were my favorite because they seemed a bit stiffer and more durable than Regina, which was popular, too. When Sun Tour started making good freewheels we were happy to start using them.
By '75 we were on the 52-42 or 53-42 overlap train, with 6-speed coming around, the exact size of the freewheel depending on the rider and the route. But when we started, somebody, I don't remember who, was getting us all into half-step.
Point being that chain rub (and chain slack, too) was never a problem on a setup like this.
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