A motorcycle major service is a comprehensive maintenance procedure that involves inspecting, replacing, and adjusting various components of a motorcycle to ensure it is running smoothly and reliably.

A typical motorcycle major service includes:

• Oil and filter change: This involves draining the old oil and replacing the oil filter.
• Air filter replacement: The air filter is checked and replaced if necessary to ensure clean air flow to the engine.
• Spark plug replacement: Spark plugs are checked and replaced if necessary to ensure the motorcycle starts easily and runs smoothly.
• Valve clearance adjustment: Valve clearance is adjusted to ensure that the valves are opening and closing at the right time.
• Brake inspection: The brakes are checked to ensure they are functioning correctly, and the brake pads and discs are replaced if necessary.
• Suspension check and adjustment: The suspension is checked and adjusted if necessary to ensure a smooth ride.
• Chain and sprocket inspection: The chain and sprockets are checked for wear and adjusted if necessary.
• Fuel system inspection: The fuel system is inspected, including the fuel lines, fuel filter, and carburetor or fuel injectors, to ensure they are clean and functioning correctly.
• Electrical system inspection: The battery, charging system, and electrical connections are checked to ensure they are functioning correctly.

Motorcycle major service is a comprehensive maintenance procedure that ensures your motorcycle is in top condition and running smoothly. It's usually recommended to have a major service performed once a year or every 10,000 miles, whichever comes first.