Change your Brakes Every 1,000–3,000 miles (varies) Replace sooner if you hear squeaking or see wear indicators

Drivetrain Match your drivetrain speed (e.g., 9, 10, 11-speed) Check your cassette and derailleur compatibility before buying

Replace when you see bald patches, dry rot, or cracks in the sidewalls. Increased punctures are a sign the tire tread is worn too thin.