In the absence of signage, what is the maximum permitted speed for a van when driving on a dual carriageway that runs within a built-up area?

On an urban dual carriageway or motorway, that is, one located within a built-up area, the generic maximum speed, without a specific sign indicating otherwise, will be 80 km/h.
We will apply the rules of motorways regarding lane use, so we must drive in the right lane, allowing the use of the rest of the lanes when traffic or road circumstances make it advisable, provided that we do not impede the progress of vehicles traveling behind.