I saw that derailluer too. it looked like something I should have 'just in case' but aside from the cage issue I think it would be a perfect for you pugeot. it will be an improvement if it shifts better, and make you happy, which is the paramount reason for have a bike yes?
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk