Safe Speed Forums

Hello everyone,

My first post, but I was interested in seeing what people though about my situation. II have to commute to work by car, (as train is hour and a half longer), on the M25. Due to petrol prices being too high I admit I do drive at 50-55mph on the motorway to help MPG.

In my defence I never stray out of the inside lane. So what are people's thoughts? does driving at 50mph on the motorway mean fuel efficiency? or is it dangerous? Any comments or advise gratefully received..

I'm assuming you're not driving through the section which is limited to about 40mph most mornings and afternoons and evenings due to incorrectly working VSL?

Welcome to the site

The things which occur to me are-

Being over taken by trucks:

Apart from not being particularly nice, be prepared to drop your speed down from 55 to assist their overtake and give them a flash when they are clear to move back over.

Being caught by faster vehicles that have not realised you are only doing 50:

Make sure you keep an eye on the vehicles behind you, be prepared to accelerate hard or take evasive action into the hard shoulder if it looks like the catching vehicle has boxed themselves in behind you due to a another vehicle in the second lane.

Passing junctions:

Watch out for vehicle taking a dive across the front of you to take the exit, make sure you are not being tailgated as you pass the junction as if you are forced to brake the guy behind may just hit you. May be worth considering passing junctions at a bit higher speed.
At the on ramp watch for the joiners travelling much faster than you, if the second lane is clear (M25 - little chance I suppose) consider using it but be prepared for the joiners to undertake so be careful when you move back over. Also as before consider raising your speed as appropriate.

In general you are going to have to be very aware of what is happening behind as well as in front and to the side, as mentioned above be prepared to accelerate if that is the safer option even if that costs you a bit of extra fuel.

These are just my initial thoughts not gospel road safety, some other members may well disagree with what I have said.

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Two things:

1. As above, you should try and pace the trucks on their limiters (~56), or they are going to be forced out into L2 to pass you, causing a 'ripple' of congestion behind.

2. Is your choice of speed based on conjecture or empiricism? In other words, have you determined this as an optimum speed for economy, or just guessed. A lot of modern diesels, for example, would be happier at 70.

I tend to drive around 50-60 on the motorway, once again to try and reduce my fuel costs. I havent yet worked out what difference it makes in my 1.8 petrol Mondeo but in my 1.9 diesel auto Galaxy with the cruise controll set to 50, I have achieved a reported (trip computer) 55mpg, this compares to a reported 46mpg when driving at 70-80.

Junctions are the biggest problem with faster traffic leaving and joining but good observations and adjusting speed prevents dangerous situations developing.

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Nick

Hi there and

Nothing at all wrong in keeping to 50 mph in L1. Folk can overtake you if they want to after all.

From my own experiences of this M25 though .. I would be counting myself lucky to be at this speed in a peak hour commute. We almost missed a ferry in Dover when we hit this in a peak .. after travelling down in the "wee small hours from "ooop Norf!"

We now use the Hull crossing .. or the Harwich one.. or the Portsmouth one .. and we've done the Poole and Plymouth ones with Brittany Ferries .. on occasions too. I have to say .. I prefer Brittany ferries despite the long sails .. which Wildy hates as she really is quite "feline" If we use Dover.. we now arevery careful as to which crossing we use and always overnight it at the ports anyway now. Less stressful.


But I think we are noticing folk driving more sedately on the fast roads up here all the same. I thus do not think you have any fears here.. and again.

_________________
If you want to get to heaven - you have to raise a little hell!

Smilies are contagious
They are just like the flu
We use our smilies on YOU today
Now Good Causes are smiling too!

KEEP SMILING
It makes folk wonder just what you REALLY got up to last night!

Smily to penny.. penny to pound
safespeed prospers-smiles all round! !
But the real message? SMILE.. GO ON ! DO IT! and the world will smile with you!
Enjoy life! You only have the one bite at it.

Have you compared your Fuel economy scores st 55MpH and 60 MpH?

Were I to 'religiously' cruise at such speeds, I'd give serious thought to some inconspicuous aerodynamic modifications.

This might be going
a bit too far,
but then again it might not.

Take special note of these 'least effort' mods: grill block, front wheel spoilers, windshield wiper air deflector, and underbody paneling. (What does 95 American MpG convert to in Royal MpG?)

Too bad an industry hasn't been made out of these types of mods ...

Stay safe!

_________________
The Rules for ALL ROAD USERS:
1) No one gets hurt
2) Nothing gets hit, except to protect others; see Rule#1
3) The Laws of Physics are invincible and immutable - so-called 'laws' of men are not
4) You are always immediately and ultimately responsible for your safety first, then proximately responsible for everyone's
Do not let other road users' mistakes become yours, nor yours become others
5) The rest, including laws of the land, is thoughtful observation, prescience, etiquette, decorum, and cooperation

Or if you want to be really radical try to persuade the government to make owning two cars more viable.

A two seat, light and efficient commuter car for most of your yearly mileage and a larger, general purpose, holiday sized, family friendly, diy stuff transporting vehicle that might not have astronomical mpg but only does a few thousand miles a year. Or, if you do not have a family, a fun weekend car.

_________________
Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Is it dangerous?.............depends on the circumstances.
Is it good driving? .......again it depends.
Are you driving safely and defensively, making good progress on or about the limit whenever it is safe to do so?

One problem on MW and DC can be created by the incompatability of speeds . If the limit is 70 will the expectations of many be that traffic will be travelling near that speed or beyond with the exception of goods vehs, or will the expectation by the majority be that one driver out of a hundred will be doing 50 or less? If you drove on test at no more than 50 on DC for a prolonged period and there was no reason why you couldnt safely travel near the limit it is poss you could fail for speed minus, remember you are travelling 15 to 20mph below the limit on the safest roads in the country.Would you drive 20mph below a 40 limit to save fuel? (If you could avoid being nicked )

The ammount of fuel you may save on your daily journey will be minute between say 50 and 65, most fuel loss is due to unnecessary loading on the engine, brief but hard acceleration,or constant speed fluctuation, by travelling at 50 to 55 you may even find yourself doing more slowing and accelerating than by travelling at 65 or even 70 so there may even be circumstances where you could use more fuel on MW by trying to be economical.Also if you overtake trucks from a start speed of 50 to 55 by the time you start feeling the wind resistance effects at that speed you will also lose more fuel over a prolonged period, Im sure you have seen vans when they almost get passed trucks when they reach that struggling point just as they pass the cab? Fuel going by the bucket load

My opinion for what it's worth......

I think that if you are keeping in Lane 1, and traffic is reasonably free-flowing you should match the speed of the other traffic in Lane 1, and this will usually be the heavy lorries most of which are speed-limited to 56 mph, although many seem to be able to acheive 60 mph (their legal speed on motorways in the UK). If you are slower than them they are forced into Lane 2, where traffic will generally be going much quicker and will then slow everybody up. This is just courtesy, of course, you are under no legal obligation, but most people don't expect slow traffic on motorways, after all they are built for speed. I don't think you will notice much difference in fuel consumption between 50 and 60.
Just match your speed so everybody is going along nice and steadily, and keep a good distance from the vehicle in front.
I go usually go along in Lane 1 on motorways at the 'prevailing speed' when traffic is heavy because I find too many people tailgating in the other lanes, and this scares me !

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Good manners maketh a good motorist

I have to say that driving on a motorway slower than a lorry these days is crazy....

You're just trying to cause an accident at that speed! IMO the word "Motorway" suggests SPEED. Therefore if you want to drive slowly or are not capable of safely doing so......take the "A" road.............or even "B" road. I'm sorry, but I live in the real world. I hate driving at 60 mph with a caravan in tow! It's a crazy law...70mph like everyone else is NO problem!..
The Motorway is not a country lane, If you can't hack it, don't use it.
Sorry........

The point of driving at less than the limit on motorways as indicated in the start of this thread has nothing to do with competance, it was brought up on the grounds of saving fuel. I can assure you you can save fuel by driving at less than 70 on the motorway, I can also confirm that you will use more fuel on A & B roads as you will need to slow down and stop more often and as should be obvious you use more fuel accelerating than driving at a constant speed.

So what do you is the minimum speed you should be driving at to prevent causing an accident on the motorway? I cant help feeling that the number of caravan crashes would increrase if they were all driven at 70.

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Nick

I would hope that you could match the lorry speed of 56mph. I think it is an un-neccessary risk to travel slower unless the road is so empty that they can pass with ease. I might ask familyman why you have a large engine cars if you are content to drive so slowly? My 1.3 people MPV carries 5 people, awkward loads and can usually achieves 45mpg at 85mph with out being streamlined. or 60mpg at 60mph. It is a great compromise, it has most creature comforts. (it looks like a pope mobile though)
It often baffels me why so many people buy expensive fast cars then doddle along at a snail pace. Then they trade them in for another newer fast car three years later? Is it the image, status symbol thing? I just dont get it. Why buy a 16v turbo GTi to drive at 50 in a 60 limit?
[rant]
The other thing I dot get is people who cover the nice seats with nasty seat covers. The car will depreciate like a stone with or without seat covers. Youve paid for them you might as well enjoy them.
[/rant]

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

Simple, a 1.3 mpv cant pull a 1200kg caravan. My 1.9 Galaxy can

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Nick

Like most other posters on here, I can't see a problem with sitting at the same speed as the big trucks. You often see "plod" doing that on routine patrol - or VOSA's "wombles", and as far as I'm aware, they don't cause accidents by doing so. All i'd say (and plenty of other have said it too) is that for this to work, you'd need to pay a lot of attention t owhat's going on behind you just in case your speed drops fractionally (say on a hill) and you force an HGV out into Lane 2 to try and pass you - which will take ages if the speed differential is small, and annoy motorists for miles behind!

I still can't quite get the general attitude surrounding this.

Somebody is doing 50mph in L1 on a motorway, another somebody comes up behind at 60, 70 or 80 and swerves out into L2 without looking at the same time that somebody is changing from L3 to L2 and these two people collide.

I still can't see in any way shape or form how the person in L1 has got anything to do with the resulting carnage, hell, he could be stopped in L2 and still not be responsible for any crashes right?

My general attitude is that I am responsible for not only my own safety but also ensuring I minimise the effects of any action of mine on others safety.

_________________
Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

The person in lane one is the root cause of the carnage.
The persons to blame or responsible for the carnage are those driving too close or without observing.
The driver in lane one could have reduced the risk.
It might be calculated that driving from Inverness to London at 50 would cause at least one near miss. Where driving the same jeorney at 56 might only create 0.5 near misses

_________________
Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

It's odd you should have quoted my post on this - I'm one of the people who is NOT suggesting it's especially dangerous - just maybe a tad selfish! I absolutely agree that the person doing 50 mght not be to BLAME for the crash but, as others have said, that doesn't mean he wasn't the CAUSE of it!

If I'm tanking round a blind bend and I see a sheep stood in the middle of the road, clearly the sheep can't be blamed for the crash but it was obviously the cause.

I don't buy that. Surely you were the cause, not the sheep.