Fuel Valve - Suzuki GSF650S Service Manual

4-4 FUEL SYSTEM

FUEL VALVE

When the engine is not operating, the fuel valve 1 is kept closed by the tension of the spring 2, which
closes the fuel passageway and stops the flow of fuel to the carburetors.
When the engine has started, negative pressure (vacuum) A is generated in the combustion chamber and
reaches the diaphragm through a passage in the carburetor's main bore and the vacuum hose. This nega-
tive pressure (vacuum) A is higher than the spring pressure which causes the diaphragm to force open the
fuel valve 1 and allow fuel to flow to the carburetor assembly.
"Fuel stop" condition
"Fuel flow" condition
VACUUM
FUEL