What is the default speed limit for buses longer than 12m?

I am currently working on this: https://wiki.openstreetmap.org/wiki/Default_speed_limits

And from the sources I have (which is sadly not the actual text from the code of laws), it seems undefined what default maximum speed limit is defined for buses that are longer than 12m.

Can you help me?

See https://www.gov.uk/speed-limits - same as <12m except on motorways, where it’s 60mph not 70mph.

Cool, thanks!

Updated the wiki page. While we are at it - the linked page does not mention this, only https://wiki.openstreetmap.org/wiki/User:Jamicu/UK_Speed_Limits#Speed_Limit_Table does:
Is it true that in the UK, if there is a i.e. 60 mph sign, it is implied that HGV may only drive 50 mph there?

**Edit: **And if it is true, is it then necessary to have a tag like maxspeed:type=GB:sign50 instead of maxspeed:type=sign to appropriately infer the speed limits for HGV etc.?

Sort of.

The look-up table at https://www.gov.uk/speed-limits only applies to the “national speed limit” (NSL) which is signposted by a black slash across a white circle. Where there’s a sign with an explicit number on it, that number applies to all vehicles, unless the NSL for that vehicle would be lower in which case the lower number applies.

https://fta.co.uk/vehicle-speed-limits explains it quite well.

(For what it’s worth, ‘60’ signs are rare, because usually where the maximum speed is 60 it’ll be signposted as NSL. You’ll very occasionally see a ‘60’ sign on a dual carriageway which has been lowered from NSL (70) because of bends or similar, but even then, lowering to 50 is more common. The other oddity is that in theory NSL is 30 in built-up areas, so there’s no need for explicit signing, but in practice 30 is always signposted explicitly.)

Ah, I see. Well, to have maximum speed limits for certain vehicles is not something unusual, many countries have this wording in their code of laws. So, this issue is outside of the concrete effort of https://wiki.openstreetmap.org/wiki/Default_speed_limits to map the regulations for certain roads (and thus find a way to tag them properly), I would say.

Any data consumers (i.e. routers) would have to have to implement a logic that 1st determines the rules specific to the given road type and then additionally caps the max speed depending on the vehicle type. It makes sense to create such a list machine-readable in the wiki as well, but at least this is out of scope for that list, as I said.

But by the way, several legislations mention this maximum speed limit for vehicle type X while at the same type making an exception for motorways. This makes this “max speed limit” somewhat harder to put to paper because either a max speed limit for a vehicle type is set for all roads, or it is not a real universal max speed limit.

There is at least one single carriageway road I am aware of the is explicitly signed as 60mph, this is the A556 between the M6 and Northwich. It is a 4 lane road which in itself is unusual.

Unfortunately no mapillary