To avoid this accelerated wear of your cassette and chain-rings, a general rule of thumb is to replace your bike's chain every 2,000 miles. Mind you, this is just a starting point. No two chains will wear at exactly the same rate because no two riders treat their chains the same. Besides your tires, your bike's chain is arguably the component that needs the most frequent replacing. Wait too long, and your chain will wear out, diminishing your shifting quality and shortening the lifespan of the rest of your drive train components.
So how often should you replace your chain? Before answering that question, it helps to understand the process of chain wear. As your chain ages, each link's internal bushings slowly lengthen. In turn, your now-longer chain puts added pressure on your cassette cogs and chainring teeth, causing them to wear faster. This also hampers shifting quality.
The 2,000-Mile Rule
To avoid this accelerated wear of your cassette and chainrings, a general rule of thumb is to replace your bike's chain every 2,000 miles. Mind you, this is just a starting point. No two chains will wear at exactly the same rate because no two riders treat their chains the same.
If you're the type who spins easy gears, meticulously cleans and lubes the chain after every ride, never rides in the rain, and weighs as much as a World Tour climbing specialist, your chain is likely to last longer than 2,000 miles. But if you never miss a meal, love to push big gears, ride rain or shine all the time, and don't even own shop rags, getting 2,000 miles out of your chain is going to be a pipe dream.
