Is letting fuel sit in motorcycle tank over winter bad?

It is not recommended to let fuel sit in a motorcycle tank over the winter. Fuel can break down over time and cause the formation of harmful deposits and sludge. This can block fuel lines, carburetors, and injectors, leading to problems with starting and running the motorcycle. In addition, letting fuel sit in the tank can cause the evaporation of volatile components, such as octane, which can affect engine performance.

To avoid these problems, it is best to drain the fuel tank before storing the motorcycle for the winter. This can be done by using a siphon hose or by disconnecting the fuel line and allowing the fuel to drain out. You should also add a fuel stabilizer to the tank before draining it to prevent the fuel from breaking down.

If you are not able to drain the fuel tank, you should try to keep the motorcycle in a cool, dark place to slow down the breakdown of the fuel. You should also avoid filling the tank all the way to the top, as this can cause condensation to form in the tank.