There could be several reasons why an old motorcycle might suddenly fail to start after repeated attempts. Here are a few possibilities:
Battery Issues: The motorcycle's battery may be weak or dead. Starting a motorcycle requires a significant amount of power, and if the battery is not providing enough voltage, the engine may not start. This is particularly common in older motorcycles with aging batteries or those that have been sitting idle for a long time.
Fuel Problems: The motorcycle's fuel system might be experiencing issues. The fuel may have deteriorated over time, resulting in clogged fuel lines, a dirty fuel filter, or a blocked carburetor. Lack of proper fuel supply can prevent the engine from starting or running smoothly.
Ignition System Failure: The ignition system, which includes components like spark plugs, ignition coils, and the ignition switch, might be malfunctioning. If the spark plugs are worn out or there is no spark being generated, the fuel in the engine won't ignite, leading to starting issues.
Electrical Faults: Old motorcycles can develop electrical problems over time. Loose or corroded connections, damaged wiring, or a faulty starter motor or solenoid can all prevent the engine from cranking and starting.
Mechanical Issues: There could be underlying mechanical problems within the engine itself. It's possible that internal components like piston rings, valves, or timing belts/chains have worn out or become damaged, affecting the engine's compression and preventing it from starting.
Lack of Maintenance: Neglecting regular maintenance, such as oil changes, air filter replacements, and valve adjustments, can lead to poor engine performance and difficulty starting the motorcycle.
To diagnose the specific cause of the problem, it's recommended to consult a qualified motorcycle mechanic. They can perform a thorough inspection and troubleshoot the issue based on the symptoms exhibited by the motorcycle.