The recommended interval for changing spark plugs in Royal Enfield motorcycles can vary depending on the specific model and engine type. However, a general guideline for spark plug replacement is typically around 5,000 to 10,000 kilometers (3,000 to 6,000 miles).
It's important to consult the owner's manual for your particular Royal Enfield motorcycle as it will provide the manufacturer's specific recommendations for spark plug replacement. The manual will outline the maintenance schedule and suggest the appropriate interval for changing spark plugs based on your motorcycle's specifications.
Additionally, factors such as riding conditions, fuel quality, and individual riding style can affect the longevity of spark plugs. If you notice any signs of poor performance, such as difficulty starting the engine, rough idling, or decreased fuel efficiency, it may be a good idea to inspect and potentially replace the spark plugs earlier than the recommended interval.