Sometimes when our mechanic replaces the chain while servicing a bike, it elicits the reaction: “Why did you replace it? It was working fine”. Here are a few notes to explain why changing the chain saves money. Why the chain wears. The chain is made of 100-114 links; each one has two plates , a rivet pin connecting the plates, and a “roller” which rolls on the rivet (so between the plates). The chain is made of hard steel, but this does not save it [...]