It is not uncommon for some motorcycles, including the Royal Enfield Classic 500, to produce a sound when upshifting gears. This sound is often referred to as a "clunk" or "thump" and can be attributed to the nature of the transmission and the design of the gearbox.
Royal Enfield motorcycles, particularly the Classic series, are known for their classic styling and design, which includes a vintage-inspired gearbox. These motorcycles typically feature a heavy-duty, long-stroke engine and a traditional "heel-toe" gear shifting mechanism.
The gearbox in Royal Enfield motorcycles is known for its robustness and durability. However, due to the design and mechanical nature of the transmission, it is not uncommon to experience a noticeable sound when shifting gears, particularly during upshifts. This sound can be more pronounced when the engine is cold or when shifting at higher RPMs.
While the sound may be a characteristic of the motorcycle and not necessarily indicative of a problem, it is still advisable to have your bike periodically inspected and serviced by a qualified mechanic to ensure that the gearbox and other components are in proper working condition.
If you are concerned about the sound or if you notice any other irregularities or issues with the gearbox, it is recommended to consult with an authorized Royal Enfield service center or a knowledgeable motorcycle mechanic who can assess your specific motorcycle and provide guidance or address any potential concerns.