What is the maximum speed a vehicle may drive in a zone with this sign?

This sign marks a bicycle zone ("Fahrradzone") in Germany. In this area, only bicycles are generally allowed to use the road, unless another vehicle has explicit permission (as in this sign, "Anlieger frei" means residents or people with a reason for access are permitted). In a bicycle zone, motor vehicles must give priority to cyclists and may only enter if the additional sign grants permission. The speed limit in a bicycle zone is 30 km/h for all vehicles. Cyclists are allowed to use the entire lane, and all road users must behave with special consideration for cyclists, enhancing their safety.