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Fri 22 Sep 2023 10:23

Using km/h speedo in UK - movilogo

When my new car came with a digital dashboard, I changed the speedometer from MPH to km/h as an experiment. Since then I kept it km/h and discovered following advantages.

I can drive in 3 digits legally. Driving over 100 (km/h) is satisfying. It is possible to drive on motorways at 120 km/h (or 125 if you stretch it) without having to fear of getting ticket.

Keeping track of posted speed limits is not an issue. The car automatically converts it. So if I am on 40 MPH road, the car displays 64 on dashboard. Also, mental calculations are not difficult - 20 MPH is 30 km/h, 30 is 50, 40 is 65, 50 is 80, 60 is 100, 70 is 110. NSL on single carriageway is 100 km/h - an easy to remember number.

As a bonus, the fuel economy is shown in km/L - a more rationale unit compared to MPG (we don't buy fuel in gallons).

Of course this is a personal thing and many others may find it weird to use km/h :-)

I need to observe next few months whether I can keep it permanently in km/h or once the fad is over I'd revert back to MPH.

Before service/MOT I need to change it back to MPH else they will not notice and will put wrong values in service book.

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Fri 22 Sep 2023 10:40

Using km/h speedo in UK - RT

All cars sold in the UK are required to show speed in kph - have been for a long time.

Why solve a problem that doesn't exist?

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Fri 22 Sep 2023 10:43

Using km/h speedo in UK - gordonbennet

Tachographs have been primarily in kms for years, with mph in smaller figures on most but not all.

Newer vehicles you are able to put a digi display of speed on the dash display via the menu, always have mine in mph and feel quite lost if i have to use a vehicle without a digital speedo.

Purchased a stand alone dash top gps digi speedo for each car, it was SWMBO getting a speed nick (awareness course fortunately) which prompted these purchases, both she and i now use them as the prime speedometer*, being on the dash top the barest flicker of eyeline to see, they handily change display colour at 50mph and again at 70mph as well.

So used to mpg figures after all these years l/km don't mean a thing to me, mileages at work in the truck are all in kms (imperial can be optioned on the dash) so i'm more used to working in kms than miles for distance but still use mpg for fuel checking...only in England could we feel so completely at home mixing and matching measures, long may we hold out and enjoy our mix n match :-)

* interestingly the analogue speedometer in both our Japan built Japanese cars are accurate to 1mph right up to 70mph, standard tyre sizes, this isn't the case in my daughter's UK built Civic which is typically optimistic.

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Fri 22 Sep 2023 10:49

Using km/h speedo in UK - movilogo

All cars sold in the UK are required to show speed in kph

Yes but those are analog speedo where MPH in large font and km/h in small fonts.

Some of them do have the option of showing digital readout but my previous car didn't have that option.

I'm talking of digitally drawn speedo where odometer also changes to km.

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Fri 22 Sep 2023 11:06

Using km/h speedo in UK - Cris_on_the_gas

Technically you are committing an offence. contrary to Construction & Use Regulations and would fail an MoT. However as you state you would change back for MoT time, no issue there. However what is the chance of getting stopped by a black rat, said rat being diligent and bothering to inspect the dashboard.

If you think it works for you then that's your issue.

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Fri 22 Sep 2023 11:38

Using km/h speedo in UK - movilogo

Technically you are committing an offence.

Why? MOT only checks for working speedometer - not units.

www.gov.uk/guidance/mot-inspection-manual-for-priv...t

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Fri 22 Sep 2023 13:53

Using km/h speedo in UK - elekie&a/c doctor

This is one of the mot anomalies. How do you check operation of the Speedometer when the mot test doesn’t involve driving the car? .

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Fri 22 Sep 2023 20:51

Using km/h speedo in UK - Chris M

Doesn't the speed register when on the rolling road for the brake test?

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Fri 22 Sep 2023 21:25

Using km/h speedo in UK - elekie&a/c doctor

You might get a flicker on the Speedo needle , but most don’t register below 10 mph . So really not an accurate test .

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Mon 25 Sep 2023 09:58

Using km/h speedo in UK - Andrew-T

<< MOT only checks for working speedometer - not units.

www.gov.uk/guidance/mot-inspection-manual-for-priv...t >>

The test manual only says that the speedo should be 'working', without further details. Should it be accurate ? The speedo on the elderly 205 I got last Christmas takes a while to wake up - when cold it shows almost zero, but after a couple of miles readings look about right (I can't really tell) but it is still slow to react to change of speed. I guess that nothing can be done to cure this problem, short of a new speedo head. But the point remains - is this a 'minor' fault at MoT ? I don't see how accuracy could be realistically checked ?

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Fri 22 Sep 2023 17:24

Using km/h speedo in UK - bathtub tom

As a bonus, the fuel economy is shown in km/L - a more rationale unit compared to MPG (we don't buy fuel in gallons).

The normal method of showing economy in litres is L/100Km. Are you sure that's not what you've got?

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Fri 22 Sep 2023 18:56

Using km/h speedo in UK - movilogo

All 3 options are available - MPG, L/100 km, km/L

A stock photo of how it appears

www.kia.com/content/dam/kwcms/au/en/images/showroo...p

This is from Kia Sorento while mine is Sportage but display looks same.

Also, the numbers in speedo are 20 units apart for lower speeds but 30 units apart for higher speeds with same gaps. May be this is only possible due to digitally drawing the image.

Edited by movilogo on 22/09/2023 at 19:00

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Sat 23 Sep 2023 11:24

Using km/h speedo in UK - Sofa Spud

We should have gone from miles to kilometres in the 1970's, when the Ordnance Survey did so. But we didn't, and since we still use mph here, I can't see any advantage in setting your speedo to kph.

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Sat 23 Sep 2023 18:06

Using km/h speedo in UK - Engineer Andy

Isn't it illegal to be driving a car in the UK with the wrong speedo settings after a certain period of time (6 moinths?) here?

When I bought my Mazda3 from Motorpoint back in early 2006, they had to change over the speedo dial from kph to mph, the odometer and trip computer settings and recalibrate, as the car was a Euro (though RHD from Cyprus) import.

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Sat 23 Sep 2023 21:56

Using km/h speedo in UK - primus 1

My Toyota shows the main readout in mph, but there is another small digital readout showing kph, not figured out why there’s a kph readout or if it can be changed..

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Sat 23 Sep 2023 22:37

Using km/h speedo in UK - movilogo

every motor vehicle shall be fitted with a speedometer which, if the vehicle is first used on or after 1st April 1984, shall be capable of indicating speed in both miles per hour and kilometers per hour, either simultaneously or, by the operation of a switch, separately.

source: www.legislation.gov.uk/uksi/1986/1078/regulation/3...e

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Sun 24 Sep 2023 08:40

Using km/h speedo in UK - RT

every motor vehicle shall be fitted with a speedometer which, if the vehicle is first used on or after 1st April 1984, shall be capable of indicating speed in both miles per hour and kilometers per hour, either simultaneously or, by the operation of a switch, separately.

source: www.legislation.gov.uk/uksi/1986/1078/regulation/3...e

Under more recent Type Approval regulations there must always be a kph indication visible - my VW's analogue speedometer has large mph figures and a small digital kph display - I can choose to use a large digital display which can be in mph or kph but the small digital kph cannot be changed

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Mon 25 Sep 2023 10:12

Using km/h speedo in UK - movilogo

The test manual only says that the speedo should be 'working', without further details

Even not having any speedo is no big deal nowadays (not talking from legal point of view). Any GPS enabled smartphone can work like a speedo. I used my bicycle GPS computer for few days in the car and it worked fine. It is USB powered with rechargeable battery. So effectively it does not require any external power (until battery dies).

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Mon 25 Sep 2023 10:55

Using km/h speedo in UK - HGV ~ P Valentine

I am sorry but I think it is a silly "experiment" when all the speed limits are in MPH, mine too can be changed to KPH and the only reason I can see a useful reason for changing it is if you in to Europe, or some other country where they do not use MPh.

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Wed 27 Sep 2023 21:38

Using km/h speedo in UK - Metropolis.

I hope we don't start adopting more metric than we have already, it's the thin end of the wedge.

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Wed 27 Sep 2023 21:46

Using km/h speedo in UK - movilogo

What is wrong with metric? Except UK and USA whole world adopted it.

Even NASA uses metric.

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Wed 27 Sep 2023 22:31

Using km/h speedo in UK - alan1302

I hope we don't start adopting more metric than we have already, it's the thin end of the wedge.

Seeing as we use it everywhere already...never understand why people get so uppity about metric....all a bit bizarre.

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Thu 28 Sep 2023 07:43

Using km/h speedo in UK - mcb100

I’m always slightly amused by tyre sizes - the section width in millimetres and the diameter in inches.
Oh, and TV screens. About the only two things I can think of that are quoted exclusively in inches.

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Wed 27 Sep 2023 23:11

Using km/h speedo in UK - Andrew-T

I hope we don't start adopting more metric than we have already, it's the thin end of the wedge.

What wedge ? Sounds like a daft Luddite comment to me. Possibly even anti-European ?

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Thu 28 Sep 2023 09:06

Using km/h speedo in UK - movilogo

Tyre size is indeed the weird one - mixing of inch and mm! Can't recall anything else with that mashup units.

Screen are often measured in cm too - along with inches.

Coming back to motoring. If we look at the recent speed limit changes, in km/h terms it went down from 50 km/h (30 MPH) to 30 km/h (20 MPH). While it feels only 10 (circa 30% reduction) in MPH terms it is 20 in km/h terms (40% reduction). This is actually a big reduction and no wonder majority are unhappy. Perhaps 25 MPH (40 km/h) would have been better choice.

Not all cars have 5 MPH speedo intervals, although for modern cars with digital speedo this is a moot point. IIRC some Porsches have only 25 MPH internals in analog speedo and drivers typically follow only digital readouts there.

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Thu 28 Sep 2023 18:34

Using km/h speedo in UK - Engineer Andy

I hope we don't start adopting more metric than we have already, it's the thin end of the wedge.

What wedge ? Sounds like a daft Luddite comment to me. Possibly even anti-European ?

Here we go again. Maybe you should examine the cost of how much it be to change every car and speed sign in the entire of the UK over. They give the limit, we know what it is, and so should visitors. Hardly difficult to translate.

Edited by Engineer Andy on 28/09/2023 at 18:36

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Thu 28 Sep 2023 18:46

Using km/h speedo in UK - Andrew-T

I hope we don't start adopting more metric than we have already, it's the thin end of the wedge.

What wedge ? Sounds like a daft Luddite comment to me. Possibly even anti-European ?

Here we go again. Maybe you should examine the cost of how much it be to change every car and speed sign in the entire of the UK over. They give the limit, we know what it is, and so should visitors. Hardly difficult to translate.

I thought we were talking about speedos, not the notion of changing thousands of road signs .....

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Fri 29 Sep 2023 05:33

Using km/h speedo in UK - expat

Maybe you should examine the cost of how much it be to change every car and speed sign in the entire of the UK over. They give the limit, we know what it is, and so should visitors. Hardly difficult to translate.

I doubt if the cost to change signs in the UK would be any greater than it was to do it in Canada, Australia, New Zealand and Eire. All of them have already done it without the world ending. Anyway as far as I am aware nobody is proposing it anyway.

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Sat 30 Sep 2023 20:48

Using km/h speedo in UK - Bilboman

Spain briefly reduced motorway speed limits from 120 to 110 km/h during a fuel crisis a few years ago and it was done pretty much overnight, with already-at-work highway maintenance crews slapping self-adhesive stickers over the existing signs. They were removed shortly after the measure ended, and it didn't bankrupt the economy. UK car speedos already show km/h as stated earlier..

It always baffled me that the UK had such a half-baked approach to metrication. We went fully decimal but only partly metric, clinging on to pints, acres and miles/mph. It's such a hopeless mishmash these days: HGV speedos and speed limits (and fines?) set in km/h. Car tripmeters show tenths of a mile but road signs show 100s of yards. More than a few low-bridge disasters have been partly blamed on signs which must be either (i) imperial AND metric, or (ii) only imperial. The temperature is given in C if it's cold but F if it's hot. One tabloid newspaper in particular has reverted to imperial measurements in every "news" article.

What's the issue here? If the whole world - around a third of its population! - is open to learning and speaking English, it's a small favour in return to use the same systems of measurement!

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Sat 30 Sep 2023 21:29

Using km/h speedo in UK - misar

Here is some Sunday light reading for those who like to work up a rage about (non-) metric roads in the UK.

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Sat 30 Sep 2023 21:23

Using km/h speedo in UK - Brit_in_Germany

Since every car for the last couple of decades is required to show kph, no change is required there. Changing roadsigns would be a relatively trivial exercise but would have costs.

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Sat 30 Sep 2023 22:10

Using km/h speedo in UK - Andrew-T

Changing roadsigns would be a relatively trivial exercise but would have costs.

As we all know, a large number were changed or added all over Wales in the last couple of weeks. I experienced some today on my regular trip into N.Wales, and I am still wondering about the logic behind the change, I can see that collisions with pedestrians should be less harmful, but beyond that I am struggling to see any real gains except perhaps in the rate of fine collection ?

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Sat 30 Sep 2023 22:20

Using km/h speedo in UK - alan1302

I experienced some today on my regular trip into N.Wales, and I am still wondering about the logic behind the change, I can see that collisions with pedestrians should be less harmful, but beyond that I am struggling to see any real gains

Maybe that is the only reason for it.

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Sun 1 Oct 2023 11:39

Using km/h speedo in UK - movilogo

Here is some Sunday light reading for those who like to work up a rage about (non-) metric roads in the UK.

Roadwork signs showing multiples of 100 yards are placed at multiples of 100 metres

That's an interesting observation. 1 yard = 0.91 m so we can assume practically 1 yard = 1 m.

I also noticed that if my sat nav is set in metric mode, the distances are quoted either in km or m (obviously) but if it is in imperial mode, it is quoted in miles, quarter miles and yards (under quarter mile).

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