The minimum engine displacement, often measured in cubic centimeters (CC), for a bike capable of long-distance touring can vary depending on several factors. While there is no hard and fast rule, a general guideline is that motorcycles with an engine displacement of 500 CC or more are typically considered suitable for long-distance touring.
Bikes with larger engine displacements tend to offer more power and torque, which can be advantageous when traveling long distances with luggage or when encountering steep inclines and challenging road conditions. Additionally, bikes with larger engines often have more comfortable seating positions, better suspension systems, and enhanced features designed to enhance rider comfort during extended rides.
Other factors such as weight, aerodynamics, fuel efficiency, ergonomics, and available storage capacity should also be taken into consideration. It's always recommended to test ride and research specific models to determine their suitability for your individual touring needs.