The maximum volume of saddlebags on a motorbike can vary depending on the specific model and design of the motorcycle, as well as the type of saddlebags used. However, a common range for saddlebag volumes is between 15 to 40 liters per bag. Therefore, in total, a motorbike can have saddlebags with a combined capacity of approximately 30 to 80 liters. It's important to note that these figures are approximate and can vary significantly based on the motorcycle and saddlebag options available.