A very worn out chain causes cassette cog teeth to be worn down – when you get a new chain, it will not mesh with the cassette, and the cassette will require replacement. This can be avoided if you change your chain for every 3,000 to 5,000 kms of riding (lower kms if you are bigger or heavier). This saves you money in the long run – regularly changing your chains will mean that your cassette is a lot less likely to require replacement when the chain is changed.
Your chain and cassette will also be in better condition if you clean your bike regularly between services. Invest some money in a good:
- Chain cleaner + paint brushes to clean your chain
- Chain lubricant