There can be several reasons why one of the cylinders in a two-cylinder motorcycle engine may stop working intermittently. Here are a few possible explanations:
Ignition Issues: One common cause could be an ignition problem. Each cylinder in a two-cylinder engine typically has its own ignition coil or spark plug. If there's a faulty spark plug, spark plug wire, or ignition coil, it can result in intermittent misfires or complete loss of ignition in one cylinder.
Fuel Delivery Problems: Issues with fuel delivery can also lead to a cylinder intermittently not firing. This could be due to a clogged fuel injector, a malfunctioning carburetor (if the motorcycle uses carburetors), or a problem with the fuel pump or fuel filter. Insufficient fuel supply or poor fuel atomization can cause one cylinder to stop firing.
Electrical or Wiring Problems: Faulty wiring, loose connections, or damaged electrical components can disrupt the electrical signals required for proper functioning of the ignition system or fuel injectors. As a result, one cylinder may experience intermittent loss of power.
Mechanical Issues: Various mechanical problems can cause a cylinder to intermittently stop working. This could include issues with the valves, such as valve sticking or improper clearance, which can affect the airflow and combustion in that particular cylinder. Problems with the piston rings, cylinder compression, or a worn-out camshaft can also contribute to intermittent cylinder failure.
Sensor Malfunctions: Modern motorcycles often rely on sensors to monitor engine parameters and adjust fuel delivery and ignition timing accordingly. A malfunctioning sensor, such as the crankshaft position sensor or the oxygen sensor, can disrupt the engine's performance and cause intermittent cylinder misfires.
Determining the exact cause of the issue requires a thorough inspection and diagnosis by a qualified motorcycle mechanic. They can use diagnostic tools and techniques to identify the specific problem and recommend the necessary repairs.