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

This road sign indicates a general restriction for motor vehicles, meaning vehicles like cars and trucks are not allowed to enter. Motorcycles, however, are usually not included in such restrictions because this sign specifically targets motor vehicles intended for passenger or goods transport on four or more wheels. Therefore, trucks and cars are prohibited, while motorcycles can use the road. Understanding this helps you recognize that when you see this sign, it restricts typical motor vehicles but permits motorcycles unless otherwise indicated.