Speed limit dual carriageway question?

[badger]

could be well off the mark as its more years than I care to remember since i had to pick up the Highway Code.[/size]But I always thought a dual carriageway was 70 so long as it had a Barrier central reservation.If not its a 60.


If the  dual carriageway is sign posted with national speed limit signs then it is 70mph whether there is a barrier or not. [if you are in / on your car / bike. if you are towing in a minibus, van , lorry etc then it is 60mph.
Confusing if you have several different modes of transport !!!!! :\