Which vehicles are not allowed to use a road sign-posted like this?

The sign shown is a prohibition for motorcycles. According to German traffic regulations, this sign indicates that motorcycles are not allowed to use the specified road.

In some cases, other vehicles such as cars or trucks may still be permitted, depending on additional signage or road conditions. Understanding this sign helps ensure that motorcycle riders avoid restricted areas, enhancing safety and compliance with traffic laws. Knowing which vehicles are affected is crucial for all road users to adhere to regulations appropriately.