Chainring life will depend on how and where the rings are used, as well as how well the drivetrain is maintained. Keep the chain and chainrings clean and well lubricated – and change the chain it when it wears – and the rings will last a long time.
Environment plays a significant role. Obviously when the rings are ridden in muddy or dusty conditions, the chain and rings will wear faster. Cyclocross and mountain bike applications tend to have shorter life than road bike applications for this reason.
Chains should be replaced when they “stretch” beyond the 0.75 mm mark as measured with a typical chain wear measurement tool. If proper care is given and chains are replaced as specified, typically the chainrings last 2 or 3 and sometimes 4 chains.
