Tip: Check your fuel filter on a regular basis and replace every 2 years.
Fuel is quite an often overlooked as a form of preventative maintenance on a motorcycle.
Check the fuel filter (if you have one) to make sure it is not clogged and looks clean and clear. Replace fuel filters every 2 years.
Check the fuel lines for weather damage and cracking, replace immediately if any is found.
Generally untreated gas only lasts (is good for) 6 months. After this time the gas starts to break down. Dispose of untreated gas older than 6 months rather than risk running it. Treated gas can last up to 2 years.
Remember when parking your motorcycle for any length of time to turn the petcock (fuel tap) to the off position. This prevents any fuel potentially leaking out and flooding the carbs or the engine.