The Suzuki GS500F has various fuel lines that are attached to various outlets, called petcocks, that are located in different areas on the bike. A petcock is a small valve that is used to control the amount of flow of fuel used by the motor. Fuel lines are connected to petcock inlet valves and outlet valves. You can connect a fuel line for a Suzuki GS500F by first removing the existing fuel lines from the bike.
Connect one end of the reserve hose to the longer petcock outlet valve for the fuel tank. Connect the other end of the hose to the bottom petcock inlet valve that is mounted on the frame.
Connect one end of the "On" or main fuel hose to the shorter outlet valve for the fuel tank. Connect the other end of the hose to the right-side inlet valve that is mounted on the frame.
Find the left-side outlet valve that is mounted on the frame and locate the bottom inlet valve that is between the carburettors. This is the hose that sends fuel to the carburettors. Connect one end of a fuel hose to the outlet valve and the other end to the bottom inlet valve.
Connect one end of the vacuum hose to the connector on the back side of the petcock valves that are mounted on the frame. Connect the other end of the vacuum hose to the connector near the inside of the left-mounted carburettor.
Attach one end of a rubber hose to the upper valve that is between the carburettors. Place the other end of the hose over the airbox. This end of the hose is open to the air.
A petcock has valves for On, Off and Reserve hoses.
If you connect hoses to the wrong petcock valves, the bike will fail to start or run properly.