Unless you are running Index shifters, skipping on only 1 cog is usually a sign that it's worn out... It's frequently the result of running on that sprocket all of the time.
BITD we used to see a lot of Maillard 5 speed 14-28 FWs with a worn out 24T sprocket??? Why the 24T???
We bought those FWs in bulk from France in wooden crates of 50 or 100. They cost us ~$3.00 USD. Changing the chain and FW was almost a standard operation on French bike tuneups back then.
BTW, the Lotus probably would have come with different wheels, not a Maillard Helicomatic hub.
verktyg