There could be several reasons why a Harley-Davidson's engine might cut off while riding. Here are a few common possibilities:
Fuel Issues: If there is a problem with the fuel delivery system, such as a clogged fuel filter, a malfunctioning fuel pump, or a blocked fuel line, it can lead to insufficient fuel reaching the engine, causing it to stall.
Ignition Problems: Faulty ignition components like a failing spark plug, ignition coil, or ignition module can disrupt the combustion process, leading to engine stalling.
Electrical Malfunctions: Issues with the electrical system, such as a faulty wiring connection, a failing battery, or a malfunctioning charging system, can result in intermittent power loss and engine shutdown.
Overheating: If the engine gets excessively hot due to a cooling system problem, it can cause the engine to shut down as a protective measure.
Air Intake Blockage: A blocked or restricted air intake system, caused by a dirty air filter or debris, can disrupt the air-to-fuel ratio and cause the engine to stall.
Mechanical Failures: Various mechanical issues like a worn-out timing chain, damaged valves, or a malfunctioning clutch can lead to engine stalling while riding.
It's important to note that these are general possibilities, and a proper diagnosis by a qualified technician is necessary to determine the specific cause of the engine cut off in any given situation.