Scottish "70mph" posted speed limits

Hi, firstly sorry in advance if this is such a rookie question that it should have been posted in the “NEW AND WANNABE DRIVERS” board, but this section had the word “Law” in it… and I’m simple like that

I think I know the answer to this one but am struggling to find anything to confirm my suspicion.
I’m revising/practising for my LGV theory test. It got me thinking about a few signs with posted speed limits of 70 I’ve driven past (in a van) whilst north of the border.

Now as far as I’m aware, unless a vehicle has special restriction currently on it (eg. carrying an abnormal load), a posted speed limit is a posted speed limit, and applies to everyone regardless of vehicle type…? Meaning theoretically a 70mph posted speed would entitle LGVs to legally travel at 70 whilst on the said road… (not that it is likely/practical to drive at 70mph but my question is more theoretical)

Now the above chain of thought seems unlikely, and my thoughts are LGVs are still legally restricted to the national speed limit of 60mph even though it’s posted as 70?

Am I correct in thinking there is some legal wording somewhere that nullifies the posted speed limit and enforces the national speed limit for LGVs? Or am I completely wrong and LGVs are entitled to travel at 70mph when it’s posted as above?

(As mentioned, my google-fu is letting me down on this one. Can’t find anything on the matter other than confused car drivers from 2015 spouting conflicting nonsense at each other when they raised the speed limit for LGVs.)

Cheers!

I’ve moved this topic here for the reason that you’ll get an answer and explanation form those who know these things.

I seem to remember that it’s called an ‘implied’ ( = default) speed limit depending on the type of road and the vehicle size/mass.

A better explanation will appear here soon.

A posted 70 limit means that is the max legal speed most vehicles can do

There are also max limits on that road for certain categories of vehicles

These are possible max limits for other types of vehicles -
Vans 60
LGVs 50 or 40

There are different max speed limits for LGVs in England and Scotland for example on single carriageways it is 50 in England and 40 in Scotland

gov.uk/speed-limits

Come at it from the other side. You should be aware of the maximum speed for your class of vehicle on the type of road you’re travelling on. If a posted speed limit is LESS than that, then that becomes your maximum speed. But there’s no way a posted speed limit will allow a greater speed than the vehicle class/road type permits.

Hope this helps,

Pete S

Thanks for the replies!

Ive seen this before on the A55 and always wondered why put it up and not a national speed limit sign?

Sent from my moto g(6) play using Tapatalk

I have noticed it on slip-roads onto dual-carriageways / motorways. In that circumstance it perhaps just clarifies that once you are on the slip-road, it is a 70 limit (for cars / small vans / some buses). It seems to hold that on direct entry to a dual-carriageway (a roundabout perhaps), it is a national speed limit sign that is displayed. Similarly, if a stretch of dual-carriageway / motorway is an enforced 40 or 50 for all vehicles, the point where this restriction is lifted shows a national speed limit sign.

I would suggest that the effective speed limit for a goods vehicle over 7.5 tonnes would be the speed limit for the road the slip-road joins on to. Of course in Scotland this depends if you are joining a dual-carriageway or a motorway.

Not presenting the above as gospel, but it seems to be logical.