What are the most essential regular maintenance tasks that should be performed to keep a road bike in good condition, and how often should they be done to prevent minor issues from becoming major problems? For example, what is the recommended frequency for checking and replacing brake pads, cables, and chain, and how can riders determine when these components need to be replaced? Are there any specific tools or equipment that are necessary for performing these tasks, or can they be done with basic bike tools? Additionally, what are some common mistakes or oversights that riders make when it comes to maintaining their road bikes, and how can they avoid them?