I show how to update a vintage 10 speed bike (Raleigh Grand Prix) to 14 speeds with Shimano SIS indexed shifting. I spread the chain stays to accommodate a wider wheel. The 5 speed hub rear wheel is replaced with another 27″ wheel with a 6/7 speed hub and 7 spd freewheel. I also replace the rear derailleur, chain. And the Huret friction shifters were replaced with Shimano indexed shifters. If I wanted to put the money into it, I could have easily spread the chain stays to 130mm, and upgraded the bike with an 8/9/10 speed hub wheel. But that would have meant going to 700c wheels. And the whole thing would have cost more.
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