M-way speed limit - What to do? - blank
Hi all:

For a number of reasons**, I drove my usual section of the M20 at a constant indicated 70 mph this morning, instead of my more normal 85ish. I stuck to this speed because I was intrigued. I joined at junction 10 and shortly after junction 9 I overtook my first car. I then carried on past junction 8 and exited at junction 7. Total distance about 18 miles(?) I didn't overtake another single car.

The motorway was pretty busy at 0745-0800 as you will imagine and I really find it surprising that so few motorway users travel at an indicated legal speed.

What should be done?

**Firstly because I was a little early out of bed this morning. Secondly because I've noticed recently that I can dramatically improve the Mondeo's fuel consumption by driving more slowly on motorways.

Hope this is food for thought and discussion and not a promt for rants of the Speed Kills - oh no it doesn't variety.

Andy
M-way speed limit - What to do? - No Do$h
I've had similar experiences on the M27-M3. I'm firmly of the opinion that for any journey under about 50-70miles, the extra speed isn't worth it due to the fluctuating flow of traffic. It's rare that you can maintain 80+ for more than a couple of minutes at a time as the speeds vary from 65-90 with the volume of traffic. Sticking to 65-70 often means I don't need to touch my brakes for most of the time on the motorway. Certainly the lack of accelerate-brake-accelerate does wonders for the MPG.

Conversely I was regularly travelling at 90-100 on the Autoroutes in France last week (speed limit is 82) and was travelling "with" most of the traffic (what little there was of it), whilst still being frequently overtaken!
M-way speed limit - What to do? - Dave_TD
And how long did the journey take you? Very much longer than normal? I'd be surprised if it did.
The motorway was pretty busy at 0745-0800


Yes, but you try the 70mph thing at any time between 0930 and about 1600, you'll find a lot more people travelling at less than 85mph, and the traffic will be flowing more cleanly too. During the rush hour a lot of motorway traffic consists of drivers who *only* use motorways in rush hours, hence the frenetic nature of the traffic flow around these times.
so few motorway users travel at an indicated legal speed


If you were travelling at 70mph, and everyone else was travelling at 70mph too, then you wouldn't be catching anyone else up, nor would they be catching you! You only overtook one car, but how many cars overtook you? As many as you'd normally overtake yourself by travelling at 85mph? I wouldn't have thought so.
M-way speed limit - What to do? - Steve S
If it's busy, I can't think that it's worth "pressing on" to the next inevitable cluster of traffic. It's not going to save much time and it will waste fuel.

On a 50 mile plus trip in light traffic it probably makes you a few minutes and doesn't do too much to the old MPG.

There is the question of concentration though. I think that a flat pace with little variation can lull you into a bit of an involuntary stupor.

So while not wanting to excessively speed I'd certainly be one for keeping up with most of the other traffic.
M-way speed limit - What to do? - blank
And how long did the journey take you? Very much longer
than normal? I'd be surprised if it did.

Not much different, I'd say about 2-3 minutes in it.
>> The motorway was pretty busy at 0745-0800
Yes, but you try the 70mph thing at any time between
0930 and about 1600, you'll find a lot more people travelling
at less than 85mph, and the traffic will be flowing more
cleanly too. During the rush hour a lot of motorway traffic
consists of drivers who *only* use motorways in rush hours, hence
the frenetic nature of the traffic flow around these times.

I think you're right. An interesting point!
>> so few motorway users travel at an indicated legal speed
If you were travelling at 70mph, and everyone else was travelling
at 70mph too, then you wouldn't be catching anyone else up,
nor would they be catching you! You only overtook one car,
but how many cars overtook you? As many as you'd normally
overtake yourself by travelling at 85mph? I wouldn't have thought so.

I was surprised how many overtook me, even when I drive at 85, I find loads of cars overtaking me on my commute both ways. It's a really boring long stretch of motorway and at commuting times lots of drivers take the p*** out of the speed limit.
M-way speed limit - What to do? - StuW
I find if i travel at 70mph on the motorway even at busy times i overtake a fair few cars and most lorries but lately i have been travelling at 60 (because money is a bit tight!) and my car fuel consumption is much better a 60 than 70 then i find i only really overtake lorries but some cars still. Personally i prefer taking it a bit easier on motorways since i don't charging in and out of lanes constantly trying to get past people its dangerous and quite stressful. I find people in the inside generally stick to speed limit and it can make for a much more relaxing motorway journey just keeping in the inside lane and doing the 60 or 70 mph. I always wonder about all those people in a rush charging up the outside lane, why didn't they just get up a bit earlier!!?

Also just curious if any truck drivers out there could clarify something for me, I thought that trucks were limited to 56 or 60 mph tops, then why do some trucks and i'm talking about the big 18 wheelers! seem to be able go 70mph plus? Isn't this illegal? Aswell as dangerous?
M-way speed limit - What to do? - Dave_TD
All UK-registered trucks newer than '88E reg have to be electronically limited to 56mph (=90kph). Most european-registered trucks follow the same rule. BUT Irish republic- registered trucks do not have the same legal restriction, nor do trucks registered outside the EU.
And the speed limiter is controlled by an electronic circuit, which means the easy way to bypass it is to TAKE THE FUSE OUT. It's that simple. Of course, when the Road Haulage inspectors check through tachograph records they will pick up on the fact that the vehicle has been driven faster than 56mph, but they don't usually take any action unless the driver has really been taking the p***.
It used to be the case that a lot of haulage operators from the north of Scotland were hanging on to their old '87D-reg wagons, because their higher average speeds meant it would take them a day less to do a return run to the south of England. However, the increased maintenance costs have more or less completely cancelled this advantage out now.
M-way speed limit - What to do? - bighammerman
Jusy a slight correction , any truck over 7.5 tonnes and registered after 1988 must be restricted to 85 kph (53 mph) this is a european law so most hgv,s on road in uk should be restricted to this, any truck pulled in a vehicle inspectorate check thats limiter does not come in till 89 kph would attract an immediate prohibition . As for "pulling the fuse " many hgv drivers have and are going to loose their licences for trying to beat the system
M-way speed limit - What to do? - No Do$h
As I understand it, an awful lot of coach drivers have found (to their horror, of course) that their limiter fuse has blown. It wouldn't surprise me if it happened to the odd lorry as well. Goodness knows how it happens.....
M-way speed limit - What to do? - Electro Man
Generally I find that is is very easy to get caught up with everybody else. You can start off doing 70 and keeping up with the general traffic, and it is not until you look down that you see you are doing 80.

I think you only need a few people speeding to "drag" the rest of the traffic up with them.
M-way speed limit - What to do? - StuW
I think what you mean electro man is what my driving instructor use to call "trying to drive the car in front and not the one your driving" basically meaning that you subconsiously keep up with the car in front and match its speed. This is bad habit to get into and one i managed to get out while learning to drive. I think comes from simply staring straight ahead at small fixed point on the windscreen and not being aware of whats going on around you or glancing at your speedo once in a while!
M-way speed limit - What to do? - Electro Man
I guess you right, there is probably a "push" effect from behind as well. It doesn't take to many people doing that to increase the average speed of traffic on the motorway.
M-way speed limit - What to do? - blank
YSD has described a phenonenon which is horribly common, especially if you drive at moderate speeds (eg 70). You will drive along for miles in the middle lane overtaking a line of trucks. When you complete the overtake and move into the inside lane the line of cars behind you, which have followed for miles, suddenly accellerate past you.
Later you catch them up again and have to pull out to lane 3 to maintain constant speed. Very irritating (calm, calm!)
M-way speed limit - What to do? - jud
That's because motorway driving is so boring, varying the speed from 70 to 85 is the only thing that helps past the time. As for travelling at 60 to save fuel with the motorway gradients were i live it's more economical to drive at a speed were by the car can maintain a constant speed without flooring the accelerator to maintain speed up long inclines.
Regarding lorry speeds when i tow the van at speeds no more than 65 (legal is 60)i am constantly being overtaken by lorries, and consider myself a menace to them, likewise old men driving at 50 to 55 are a menace to me.
M-way speed limit - What to do? - Dave_TD
Regarding lorry speeds when i tow the van at speeds no
more than 65 (legal is 60)i am constantly being overtaken by
lorries, and consider myself a menace to them, likewise old men
driving at 50 to 55 are a menace to me.


The root causes of this problem seem to be partly the inaccuracy of car speedo's and mostly the vastly different PWRs (Power to Weight Ratio) of lorries on the road today. Also a lot of people fail to understand the different rules concerning use of lanes and speed limits where lorries are concerned.
Firstly, the speedo on my Skoda reads about 8% fast, I have checked it against several different calibrated sources and always had the same answer. Therefore when travelling alongside a limited lorry travelling at 56mph I would expect my speedo to read 60-61mph, this is what happens.
Secondly, most large lorries on the road today have between 350-600bhp, and between 1,500-2,800Nm torque, which means that (especially when less than fully loaded) they may not slow down on hills as much as you expect, also with semi-automatic gearboxes and no need for double declutching they accelerate a lot harder than they used to! I have been taken by surprise more than once when overtaking a lorry just after a roundabout only to find his speed has matched mine up to 56mph.[1]
Thirdly, only lorries of over 7.5tonnes gross weight are speed limited and prohibited from using the outside lane of a 3+ lane motorway. When a lorry comes past you doing 70mph+, it most probably is only a 7.5t vehicle.[2]

[1] Ok, ok, I know the Octavia SDi takes 19 seconds to hit 60mph from a standing start, but it's still quite something being held off by 60ft of articulated Scania.

[2] If it's definitely a lot lot bigger than 7.5t, at least natural selection will mean he won't carry on driving like that for very long before he gets caught or wipes out. Other lorry drivers are just as likely, if not more so, to report behaviour like that.
M-way speed limit - What to do? - dave18
Trying to do 80/90 (whatever) for the hell of it in busy traffic is pointless, one reason being the traffic will bunch and slow at regular intervals as has already been pointed out. But in my opinion its a different story in quiet, safe conditions. Not that Im condoning silly speeds, just suggesting the 80/90 cruise in such circumstances makes more sense.
M-way speed limit - What to do? - Dave_TD
It's all relative. When I'm on a motorway in the car (as opposed to the transit or one of the 7.5 tonners) I tend to travel at around the 75th-80th percentile of car speeds, that is to say I would expect to be overtaking 3 or 4 times as many cars as are overtaking me. I don't stand out to anyone observing as being obstructive and slow, nor as being quicker than the majority of traffic, just as being present but unobtrusive. I don't get wound up, hot under the collar or frustrated by heavy traffic, in fact I prefer a long motorway drive to an A-road journey no matter what the traffic's doing! Although I still go M1 J24 - A50 - A500 - M6 J16 rather than through Brum.
M-way speed limit - What to do? - Morris Ox
I spent two-and-a-half years doing a daily commute from Nottingham to Leeds, sometimes A1, mostly M1.

After a few weeks I got into the habit of puddling along in the inside lane all the way doing 65-70.

Probably cost me half an hour a day overall, but it was a price worth paying for being calm and collected after a daily trek, for the increased economy and the reduced wear and tear.

So leave early, cruise, stay calm.
M-way speed limit - What to do? - Wales Forester
Slightly wandering off topic, but just to add to DTD's comments, how many Backroomers are aware that buses and coaches weighing 7.5tonne and under are legally allowed into lane 3 on the motorway?
Not common knowledge I believe, and quite a shock if you're batting along in lane 3 and are confronted by a 33 seater moving out in front of you!
M-way speed limit - What to do? - HF
I really find it surprising that so few motorway users
travel at an indicated legal speed.
What should be done?


This is not a rant of the 'speed kills' variety, and I hope it doesn't come across that way. I'm just a little confused.

Andy S, you sound worried that so few people drive at a legal speed on motorways, and are asking what can be done about it; and yet you say your own usual speed is around 85?

If I am being dense then I'm sorry ;)
HF
M-way speed limit - What to do? - blank
HF:
Not dense at all, and it's interesting that nobody has suggested what should be done. I don't know what the answer is either.

I am interested that such a huge proportion of car drivers on this particular possibly unrepresentative piece of motorway, were breaking the law. I'm concerned that such widespread blatant lawbreaking cannot be good for a society.

Hope this explains my thought process

Later!
Andy
M-way speed limit - What to do? - HF
Hi Andy,

Please take this in the slightly TIC manner in which it is intended ;)

I agree widespread lawbreaking is not good for society - my question came from the fact that, until you realised it was less economical, your own general practice was to drive at 85! The last thing I want (like you) is a speeding debate, but that's why I was questioning what you said ;)

I *do* understand your thought process, and I'm sure you drive perfectly safely at 85, but that's probably what everyone else thinks too! And I'd guess the reason that nobody has actually suggested what should be done is that most people would prefer not to be limited stringently to 70mph?
HF
M-way speed limit - What to do? - CM
I am not sure if it is the case or not, but from experience of seeing a police car on the m'way, if we all drove at 70mph the m'way seems to clog up. I am not sure if this is just the affect of those going more than 70mph being held up by those doing 70 (thus a jam) or not.

I am not sure what the view of the police is on this and whether they really want everyone to stick to 70mph or not.
M-way speed limit - What to do? - dave18
As ive posted before, Ive been pulled twice on the motorway. Once at 97 on a sunny afternoon on the M32 (coming back from Bristol) which resulted in a verbal slap on the wrists for doing that speed in a battered old Polo and once having travelled at an indicated 90ish in mothers Accent on the M62 around lunchtime. Police bike pulled up along side me at the red lights at the roundabout junction of the M62/M57 and told me to put my seatbelt on (I had taken it off momentarily, the tensioners had jammed or something IIRC.)
I once was doing 95ish for a brief stretch when passing som bunched traffic on the M6 near Warrington. BM 5 series glued to my back bumper.I saw the patrol car on a bridge, slowed (scary experience but probaby scarier for the idiot exec-in-a-hurry) and grabbed a space in the middle lane. Patrol car went flying after the BM that had clearly been floored as soon as the annoying boy racer in front of him had got out of his personal pace. Some examples like this amuse me.
Point of this post is I think the traffic police are generally reasonable. Some of the documentaries about them portray them as jobsworths. From my own motorway exerience I don't think they wish everybody to travel at 70. Lets face it theyd rake it in if 70 was enforced rigidly. When a Range Rover sits in the inside lane causing the traffic to bunch and do precisely 70 behind it, Im sure its a game to them.
M-way speed limit - What to do? - Steve S
I always ease past them if they are doing dead on 70 - never had a problem. Obviously road conditions and visibility would come in to it. There are times when 70 is too fast.
M-way speed limit - What to do? - slefLX
I am not sure what the view of the police is
on this and whether they really want everyone to stick to
70mph or not.


I don't think the police do want everyone to stay at 70. I always do (indicated) 70, yes, I know, boring law-abiding and possibly a tad slow - anyway, one particular day I was in the 3rd lane doing my normal 70 overtaking slower vehicles in the 2nd lane and I was aware of a white 4x4 staying a reasonably distance behind me. On closer inspection I realised it was a police car and when I had the opportunity (that I was looking for anyway) to move back into lane 2 the 4x4 obviously overtook me at at least 75-80mph. If it's a case of leading by example it seems that's the speed we're all supposed to do.

M-way speed limit - What to do? - MarkyMarkD
I don't think the police do want everyone to stay at
70. I always do (indicated) 70, yes, I know, boring law-abiding
and possibly a tad slow - anyway, one particular day I
was in the 3rd lane doing my normal 70 overtaking slower
vehicles in the 2nd lane and I was aware of a
white 4x4 staying a reasonably distance behind me. On closer inspection
I realised it was a police car and when I had
the opportunity (that I was looking for anyway) to move back
into lane 2 the 4x4 obviously overtook me at at least
75-80mph. If it's a case of leading by example it seems
that's the speed we're all supposed to do.


I can think of nothing which causes more motorway hold-ups, and accidents, than people who overtake in the outside lane at 70 mph (or even worse, indicated 70 mph i.e. 65 or less) - and as a consequence, take MILES to get past the cars in the middle lane travelling 1 mph slower.

If you have to drive at 65 mph, for goodness' sake stay in lane 2 (or 1) and speed up to a sensible speed if you HAVE to move out to lane 3 to overtake.

In fact let me generalise some more. VIRTUALLY ALL motorway jams (excluding ones caused by accidents or roadworks) are caused by people who overtake with too little speed differential AND/OR stay in lanes 2 or 3 when they should have pulled back into lane 1 or 2.
M-way speed limit - What to do? - smokie
MarkyMarkD - with you on this, especially those who "stay in lanes 2 or 3 when they should have pulled back into lane 1 or 2."

IMHO this is the single biggest cause of lane 3 congestion (and hence tailgating) on the motorways today.

M-way speed limit - What to do? - slefLX
How am I causing a jam if I have already moved out from lanes 1 and 2 because other traffic in front was moving slower than me? OK, barring the fact that I had a police car behind me on that particular occasion I *never* stay in lanes 2 or 3 for longer than necessary so that others can get past and when I'm in those 'faster lanes' I'm constantly on the lookout for those who want to run me into the ground and on those occasions I'll make even more concerted effort to get back into lane 2 or 1. I know I don't travel on Britain's busiest motorways and maybe my driving style would be different if I did but I can only talk/write from experience and I suppose I'm lucky in that I haven't had the misfortune to come across any lane 3 jams or congestion because people are 'only' travelling at 70.
M-way speed limit - What to do? - Obsolete
I can think of nothing which causes more motorway hold-ups, and accidents, than people who overtake in the outside lane at 70 mph

I can't fathom this comment.
M-way speed limit - What to do? - danwave@lycos.co.uk
People drive past the speed limits as it is exciting or they just conform.

I personally used to drive fast (100mph). However, I paid for it in diesel.

I was reading an article, and it said by driving at 50MPH instead of 70MPH you can gain 30% in fuel economy, wear out the tyres less by up to 50% and make the engine last longer.

So, I decided to drive on the motorway at 50MPH. Only some people followed this speed, creating a nice barrier behind me. It took 200 miles of motorway speed to relax at this very slow speed, as it is not easy. It may seem really easy, but very few can stand it for more than an hour. Fuel consumption increased (the gauge never moved for 200 miles) and the tyres lasted 40,000 miles as oppose to 25,000 miles. Overall savings are therefore very high indeed, bu very few do it.

To maintain this very low speed, I deliberately put a police like stripe at the rear of the car. Not only do people keep their distance as they think it is a police car, it also adds safety.

I now always drive at 50-60MPH and save lots of money!
M-way speed limit - What to do? - daveyjp
It's OK staying at 50-60, but when a wagon overtakes you with a max speed of 56 mph thus causing two lanes to be doing 56 mph it doesn't half cause a tailback. As far as I'm concerned if any car is overtaken by a 38 tonner in free running traffic they are not going fast enough and should be charged with impeding the passage of other road users. I've talked to truck drivers about this and they agree - the worst thing they can come across is the old boy doing just over 50 mph in the inside lane coming up to a hill, they need momentum to get up the hill and don't need the distraction of a slow vehicle to force them to change lanes, thus slowing down another whole lane of traffic.

M-way speed limit - What to do? - jd
danwave,

Very commendable I'm sure....

but how on earth do you keep awake ?

JD
M-way speed limit - What to do? - Dave_TD
And how far do you drive like this in a year...?

(Just so I can calculate how often I'm likely to overtake you!)
M-way speed limit - What to do? - jud
Dan,
the men in white coats have arrived, good bye.
M-way speed limit - What to do? - Steve S
Indeed. Driving at 50 on a motorway you won't encounter many delays - you'll cause plenty, but there we are.
M-way speed limit - What to do? - Dave_TD
To maintain this very low speed, I deliberately put a police
like stripe at the rear of the car. Not only do
people keep their distance as they think it is a police
car, it also adds safety.
I now always drive at 50-60MPH and save lots of money!


I have to say, very occasionally I'll approach a car doddering along the motorway at 50mph or so, with some kind of reflective marking (red tape etc) on the back bumper or round the back window... (No offence to vansboy here, but they do tend to be Montego estates or Maestro hatches!!) And the thought that goes through my mind is: (politely)
That the car is being driven by somebody nearing the end of their driving career, who is less likely than average to be able to cope with modern motorway driving conditions, and more likely than average to do something really stupid and/or dangerous through lack of observation or appreciation of the situation they find themselves in.
If you feel the need to adorn your car with extra reflective material, (in the same way as some drivers feel the need to hide behind "P" plates) then you recognise that you pose a risk or hazard to other road users, but are unwilling to modify your own driving habits to reduce that risk.
M-way speed limit - What to do? - dave18
Im intrigued by the comment about the engine lasting longer and the fact that such a stupid claim was actually published somewhere!
M-way speed limit - What to do? - BrianW
If you want to drive at 50mph on a motorway that's fine.
Why not drop to 30mph and get even better consumption?

But if by doing so you are "creating a barrier" then IMHO that is inconsiderate driving, effectively reduces the road by one lane and may be causing accidents behind as people pull out of your "tail" to overtake.

Part of good driving consists of being aware of the needs of others. I am not usually a particularly fast driver, but if I become aware of a build-up of vehicles behind me and I am below the legal limit I will either speed up so as not to impede them or slow down on a straight stretch to let them past.
M-way speed limit - What to do? - BigBoab
Many years ago, my driving instructor was a former traffic cop. He said that the basic rule that traffic cops used for speeding is that within +10% of the legal limit is okay. Anything above that was likely to get you stopped. Of course, this was in the days before Gatsos so I don't know if it still applies. He said that when stopped always say that you were doing an 'indicated' speed.

His final advice was to carry a disposable camera in the car to take evidence photos if you were ever involved in an accident.
M-way speed limit - What to do? - Black Rat
Thought I'd just point out that the general rule of thumb is +10% + 2mph which equates to 78mph on the motorway.
A couple of years ago when I was patrolling the M25 we would not consider stopping a car under 85mph according to our calibrated speedo unless is was being driven in a manner not suitable for the conditions.
Gatso cameras are different in that there is no discretion possible and in many places e.g. roadworks are set tightly to the 10% + 2mph. Other locations may be set above this but you won't know.
M-way speed limit - What to do? - smokie
Forgive me, doesn't 70 + 10% = 77, then plus 2 = 79mph?

pp Carole Vorderman
M-way speed limit - What to do? - volvod5_dude
You have to make allowances, Police and mental arithmatic.
M-way speed limit - What to do? - No Do$h
This begs a question. If you want to travel at 50, why use a motorway and not one of the many A roads that shadow our motorway network (and often offer shorter journeys due to their lower environmental impact allowing them to take more direct routes)
M-way speed limit - What to do? - Gen
think black rat means 70 + 10% + 2 = 79 therefore 78mph is "safe" and 79mph is not...thanks for that...good to know, not that i trust my speedo to a mph or two
M-way speed limit - What to do? - HF
>>If you want to travel at 50, why use a motorway and not one of
>>the many A roads that shadow our motorway network (and often
>>offer shorter journeys due to their lower environmental impact
>>allowing them to take more direct routes)

Yes absolutely, couldn\'t agree more. I avoid motorways like the plague, but have on occasions taken less time to get to a destination than my motorway-loving acquaintances.
HF
M-way speed limit - What to do? - Blue {P}
On the A1 yesterday they switched on the Matrix signs with a 70mph speed limit. I remember someone else on this board said this happened near them but I didn't beleive that they would actually use the Matrix signs to display the 70mph limit... Seems they do, so that means it's OK to do 80ish0 normally then and just stick to 70 when they ask you to?

I'm confused...

Blue
 

Value my car