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Why your speedo isnot accurate.

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Arborbridge
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Re: Why your speedo isnot accurate.

#275264

Postby Arborbridge » January 5th, 2020, 10:24 am

Lootman wrote:
didds wrote:
Arborbridge wrote:Hopefully, though, not in the middle lane ;)

but maybe if the inside lane is full of trucks doing 50mph... :-)

Yes, as I recall this entire issue arose because someone claimed that the most relaxing way to drive was in the left lane. And I don't think that is the case at all. It's full of trucks, as you say, with resultant loss of visibility, plus potentially smoke, fumes, spray and so on. Plus you constantly have traffic merging from your left.

The middle lane is more relaxing. It's not a problem when the left lane is a convoy of trucks, as noted. But it is when the road is open and quiet, when nobody would need to "hog" the centre lane anyway.

On crowded motorways then it is most relaxing to minimise your number of lane changes, even if that means accepting that your speed may vary as a result because of prevailing traffic.


I hope we can all agree that "hogging" the middle lane at a low speed is a poor show. I wonder if people who do this realise what tailbacks they often cause and similarly, the nuisance value generated when an entire inner lane is left unused for miles on end. These people are a menace and should receive hefty fines.

Maybe the solution is to make it clear that overtaking on the inside is not only permitted, but encouraged to neutralise the effect. Perhaps a really "smart" motorway could book them and take charge of their steering wheel until they comply :lol:

Arb.

jackdaww
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Re: Why your speedo isnot accurate.

#275283

Postby jackdaww » January 5th, 2020, 12:10 pm

didds wrote:
Arborbridge wrote:
richlist wrote:Very interesting.

But if I want to drive at 65mph and that's what my speedometer is indicating that's what I'm gonna do regardless of holding up any caravans.



Hopefully, though, not in the middle lane ;)



but maybe if the inside lane is full of trucks doing 50mph... :-)

didds


==========================

i wonder what the middle lane other planet inhabitants think when i pass them on the inside - with my caravn in tow ?

:lol:

Lootman
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Re: Why your speedo isnot accurate.

#275334

Postby Lootman » January 5th, 2020, 5:47 pm

Arborbridge wrote:
Lootman wrote:
didds wrote:but maybe if the inside lane is full of trucks doing 50mph... :-)

Yes, as I recall this entire issue arose because someone claimed that the most relaxing way to drive was in the left lane. And I don't think that is the case at all. It's full of trucks, as you say, with resultant loss of visibility, plus potentially smoke, fumes, spray and so on. Plus you constantly have traffic merging from your left.

The middle lane is more relaxing. It's not a problem when the left lane is a convoy of trucks, as noted. But it is when the road is open and quiet, when nobody would need to "hog" the centre lane anyway.

On crowded motorways then it is most relaxing to minimise your number of lane changes, even if that means accepting that your speed may vary as a result because of prevailing traffic.

Maybe the solution is to make it clear that overtaking on the inside is not only permitted, but encouraged to neutralise the effect.

Yes, I agree. If undertaking was legal and normal, then hogging the middle lane would be a lot less annoying to others. Whilst if "hogging" was legal and drivers could pass on either side then the problem is mitigated. So they are really two sides of the same coin. Currently we allow neither but we could allow both.

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Re: Why your speedo isnot accurate.

#275350

Postby jfgw » January 5th, 2020, 6:31 pm

I recall that the subject of undertaking was brought up on TMF and someone linked to a report that said that the style of driving specified by The Highway Code (drive in the nearside lane unless overtaking, and only overtake on the offside) was the safest, especially at higher speeds. The style whereby one keeps to one lane and passes either side was much more sensitive to speed, i.e., an increase in speed results in disproportionately more casualties.

I suggest that a significant safety factor is that of drivers obeying the same set of rules. If you are driving in a country where you may pass either side, drive in accordance with their rules. However, if you are driving in the UK, driving in accordance with The Highway Code is likely the safest option.

A more obvious example is that, all else being equal, it is safer to drive on the left than it is the right. The overriding factor, however, is what everyone-else on that particular road in whatever country you are in is doing.


Julian F. G. W.

Arborbridge
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Re: Why your speedo isnot accurate.

#275442

Postby Arborbridge » January 6th, 2020, 7:53 am

jfgw wrote:I recall that the subject of undertaking was brought up on TMF and someone linked to a report that said that the style of driving specified by The Highway Code (drive in the nearside lane unless overtaking, and only overtake on the offside) was the safest, especially at higher speeds. The style whereby one keeps to one lane and passes either side was much more sensitive to speed, i.e., an increase in speed results in disproportionately more casualties.

I suggest that a significant safety factor is that of drivers obeying the same set of rules. If you are driving in a country where you may pass either side, drive in accordance with their rules. However, if you are driving in the UK, driving in accordance with The Highway Code is likely the safest option.

A more obvious example is that, all else being equal, it is safer to drive on the left than it is the right. The overriding factor, however, is what everyone-else on that particular road in whatever country you are in is doing.


Julian F. G. W.


Quite agree. This is the problem for the authorities in any discussion - and why there will be no change. Maybe the alternative of fines might discourage people from lane hogging, but there will be difficulties with drawing up rules - e.g. to combat the argument "I was in the middle lane because I draw out to over take the next vehicle" (but that vehicle is a mile ahead, and you've already been in the middle lane for two miles!)

Arb.
.

Dod101
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Re: Why your speedo isnot accurate.

#275444

Postby Dod101 » January 6th, 2020, 7:59 am

Bing one who prefers to obey the law (quite apart from the fact that I am also one who prefers not to get points and/or a fine) I will no longer undertake, but any lane hogger is likely to get a few flashes of my lights from me, especially if it is a two lane highway and he is hogging the outside lane at 60 mph.

Dod

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Re: Why your speedo isnot accurate.

#275458

Postby bungeejumper » January 6th, 2020, 9:34 am

Dod101 wrote:Bing one who prefers to obey the law (quite apart from the fact that I am also one who prefers not to get points and/or a fine) I will no longer undertake, but any lane hogger is likely to get a few flashes of my lights from me, especially if it is a two lane highway and he is hogging the outside lane at 60 mph.

Sorry to bang the same old europhile drum again, but with the notable exception of Paris (where lane rules count for absolutely nothing!), slow outside-lane hogging on motorways is another of those things that I very rarely see in France. (Along with motorway speeding.) Maybe it's that the country's traffic cameras are better than ours, or maybe it's just that most motorways are two lane affairs anyway, where there's less opportunity for undertaking. Then again, maybe it's that French drivers will always flash you if you're in their way in the outside lane. ;)

In short, you can drive for 500 miles on the autoroute without seeing anything very irregular going on, and that means you arrive fresher and more relaxed. Alas, then you get onto the local roads, which are a less forgiving and more dangerous place altogether........ :lol:

There's one respect in which France is like America, though. Namely, that both have twice the number of road deaths we have, in relation to distance travelled. (France 6 deaths per billion km, US 7, UK 3.4). https://read.oecd-ilibrary.org/transpor ... 2-en#page1 . Neither country has much to teach us about how to drive safely.

BJ

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Re: Why your speedo isnot accurate.

#275505

Postby jfgw » January 6th, 2020, 12:53 pm

bungeejumper wrote:There's one respect in which France is like America, though. Namely, that both have twice the number of road deaths we have, in relation to distance travelled. (France 6 deaths per billion km, US 7, UK 3.4). https://read.oecd-ilibrary.org/transpor ... 2-en#page1 . Neither country has much to teach us about how to drive safely.


The statistics specifically for motorways would be more revealing. They are by far the safest roads overall. The speed limit on the French Autoroutes is usually 80mph unless it is raining.

I haven't driven in France for many years. Is tailgating as bad as it used to be?

Julian F. G. W.

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Re: Why your speedo isnot accurate.

#275507

Postby yorkshirelad1 » January 6th, 2020, 1:02 pm

AsleepInYorkshire wrote:SAT NAV VS. SPEEDOMETER: WHICH SHOULD I TRUST?

Garmin

AiYn'U


And I wonder what the cameras and speed guns use.
I think I stick with the GPS, set the cruise control, and pottle along at about 1mph +/- the applicable limit.

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Re: Why your speedo isnot accurate.

#275512

Postby Meatyfool » January 6th, 2020, 1:23 pm

I think I need to recheck my speedo to my GPS:

I set my speed limiter to limit+10%, so I do 55 speedo in a 50 limit and 77 speedo on a motorway.

I think only one poster has indicated an excess as large as this, which makes me want to double check!

On 30 roads, my 33 speedo normally shows as 29/30 on roadside speed indication devices.

Meatyfool..

bungeejumper
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Re: Why your speedo isnot accurate.

#275516

Postby bungeejumper » January 6th, 2020, 1:28 pm

jfgw wrote:I haven't driven in France for many years. Is tailgating as bad as it used to be?

Good question. In my experience, no, but my A road driving tends to be rural so it might not be representative.

First up, general speed limits in France have now been reduced from 90 kmh to 80 kmh, and many towns are on 30 kmh (roughly 20 mph), and that has helped matters, if only because it has served as a general reminder to a population that needed reminding. :twisted: I don't see that many people doing silly-buggers speeds lately.

Second, the flics are making good progress against drink-driving, which can't be a bad thing. I was stopped and breathalysed at the roadside a couple of years ago, not because I was driving badly but because they were stopping every car. (I scored zero on the meter, which surprised me a bit because I thought even teetotallers had a bit of fermentation-fizz in their veins all the time?) In Britain, of course, the police don't have the power to breath-test without cause for suspicion.

Mostly, though, it's that France now has a licence points system like ours. One of the bolder initiatives is that, after any fatal accident, everybody within a reasonable distance of the incident gets a point on their licence, guilty or innocent. It might not be fair, but it sure as hell concentrates the mind.

A final note on tailgating and suchlike. I'd always assumed that some French drivers tailgated British cars because they were still fighting the hundred years war, but a friend with a locally-registered car says they're as brutal to each other as they are to us anglos.

On the whole, I reckon the French authorities deserve quite a bit of praise for improving driving standards in the long term. Sadly, though, the halo has been slipping a bit in the last few years and the accident stats are creeping back up again. :(

BJ

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Re: Why your speedo isnot accurate.

#275786

Postby Meatyfool » January 7th, 2020, 4:06 pm

Checked my speedo against my iphone SE + Waze app last night on the way home:

First number is what I set my speed limiter too, second is what the satnav indicated:

33, 29 or 30
44, 39
66, 59

So I was correct in that I can set my speed limiter to speed limit + 10% and stay within the "real-world" speed limit.

Meatyfool..

PS: Just realised I have been on TMF/TLF for over 20 years!


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