Originally Posted by
HillRider
Early Campagnolo downtube friction shifters were notorious for doing just that and causing ghost shifting. You had to tighten the D-ring every couple of rides. Simplex sold a lot of their "Retrofriction" shifters because of this.
True, but it was mainly a problem with the B and C line shifters that used an outer plate with a tab that went down to the back plate. The long tab had some give and the outer plate walked back and forth loosening the wingnut. The A line Record shifters used a side flatted central shaft (still used on lever bosses,
like the one here), and mating outer plate which was very reliable.