JRN wrote: ↑Thu Jun 10, 2021 08:24
Yep. And the 25 mph speed limit is widely used in cities and residential areas in the US too.
I'm not sure how widely 40 km/h is used in Europe, they seem to be favouring more and more 30 km/h (18.5 mph) zones in cities in many countries.
25 mph is a far more comfortable speed to drive for any extended period than 20, which has very poor compliance.
It's just a shame that either metrifying or introducing 5 mph increments to speed limits would be such a huge shake-up to our existing system, would be very hard to implement.
We must be just about the only country in the world to use MPH in only 10 MPH increments.
Why would you want greater precision than 10 mph / 20 km/h increments? Once you get into the 5 mph / 10 km/h increment range, you're approaching the margins of error inherent in your measuring device and your visual ability to accurately read your speed from the dial (I appreciate that isn't relevant if you have a HUD that tells you your precise speed in figures).
More importantly, you are encouraging drivers to place too much emphasis on obeying the speed limit for its own sake, and not enough on driving at a suitable speed for the conditions.
I can only speak for my corner of metric Europe, but here 40 km/h is the commonest urban speed limit these days, at least round me (i.e. in the hinterland of a big city). To all intents and purposes, Sweden no longer really has default speed limits in any context and you have to read the roundels. If you look on "how to drive in country X" lists provided by insurers, the AA etc., they'll tell you that the motorway limit is 120, NSL on single carriageways is 70 and urban is 50. But round me at least, I have to drive about an hour in any direction to get a motorway with more than 100 (the E6 through Tingstadstunneln is as low as 70). NSL on country lanes is indeed 70, but unless you want to rip your sump off I don't advise it. Main roads in the countryside tend to be up-limited to 80 or 90, and signed 70s are not so much the default as a conscious decision to lower the limit for junctions etc. 50s in towns are a dying breed, and 40 is the norm, with 30 on residential streets.
As to increment size - the only other Western country to use mph at all is the US, and while speed limits there *may* end in a 0 or a 5, I don't think most places use both, at least not in such a way that you will go from 25 to 30 or similar. What you might get is, say, 25 in towns, 55 on rural S2s and 80 on freeways, but that's not really the same thing.