Safe Speed Forums

In the general scheme of things it's broadly true, though.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

Weepej, I really can't imagine how limiting someones top speed by 10MPH can help them not miss a turn off. I think if you are dozy enough to miss your turn off, you would do it whether you are doing 80,70 or 50MPH. In fact you are more likely at 50MPH ,I would guess, as boredom and lack of anticipation starts to take over.

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

Business has a range of measures to plan for with respect to driving within the business.
Arrival time and time-for-journey are one aspect.
With nearly half of road accidents involving a vehicle/driver who is working, the employer has to consider driver fatigue and probability of accident (it's called a "risk assessment", and is mandatory (and simple)).
Work your way around this: The driver is working and his/her employer is responsible for the amount of driving they do, that falls within the health and safety at work remit.
By all means drive at 80mph if you want to, it is legal and you are capable of so doing.
However, not all are capable of so doing. Reaction times vary, as a persons ability to concentrate does.
People are fond of the "motorways are the safest roads" theme....well, they are. But accidents on them are frequently horrific.
My vehicle manufacturer states that at 30mph the vehicle will return a fuel use of 28mpg, and at 56 will do 38mpg, and at 70 will do, again, 28 mpg. The figures are near to the ones I get driving.
I have a friend with a tdci focus, who gets 60mpg at 60 mph, and 45mpg at 70 mph (which he has to drive at fairly often because of the particulate filter and its cleaning routine....)......
Fuel [diesel] is now 149.9/ltr here.....general consumption (over the country) is dropping....down by around 20% compared to a few years ago. The price is going to go higher. Even if someone/company comes up with a cheaper fuel it will be taxed to a price comparison. If lpg gets used more, it will be taxed higher.
It's what you get in an authoritarian state, which is what the EU (us) is.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

Jom, where does your manufacturer state that you car will do 28 to the gallon? He's not required to take measurements at that speed, so I'm curious as to why they're even quoted? My experience of (mainly modern diesel MPVs) is that they actually give their best fuel consumption at between 20 and 30! I've done this on quite a few cars now and they all end up the same. Forget "top gear at peak torque" and all that malarkey - it's actually MUCH lower than that these days. As diesel engines get ever more efficient, their fuel consumption is getting closer to the simple "the less work they're doing the less fuel they're using" rule. If you don't believe me, try zeroing the trip computer, setting it to display average consumption, and drive for a couple of miles at a constant (say) 56. Then do the next couple of miles (hopefully under similar road conditions) at (say) 40. See if the average consumption has gone up or down by the end of the second couple of miles. Doesn't matter of you have to drop down to 5th or even 4th. I've just come back from Newcastle today along the A69. Average consumption doing 60-ish was about 45 to the gallon. Then I came up behind an unusually law-abiding artic which was doing 40. There were no overtaking opportunities for abut 10 miles - at the end of which my average consumption was nearer 50 to the gallon. I've seen it time and again on my trips to Scotland. Tank up the M74 at (cough! - rather not say! ) and then hit the M73 in the morning rush-hour and watch the average consumption improve. By the time I get on to the M8, the traffic is MUCH heavier - lucky to be bettering 20 MPH at times, yet the average consumption IMPROVES FURTHER!

They're quoted because THAT'S WHAT I GET.
Never mind government initiated figures, those are what *I* get over tens of thousands of miles.
Never mind the averaged econometer figures, those are consumption figures that the vehicle does while being driven by me.
They are also the figures, near enough, given in the manufacturers leather-bound operator manual....
HERE are loads of vehicle fuel figures that owners input......the real consumption.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

Ah, ok, it's just when you said "My vehicle manufacturer states...". I thought you were talking about the vehicle manufacturer's claimed figures. If they're your figures, fair enough, but are you really telling me you've done 10s of thousands of miles at a constant 30?! Ta for the spreadsheet link, but I can't really get anything useful out of it. I take it that's some sort of site where owners put in their own claimed fuel consumption figures? Presumably they are their average figures? I see one or two seem to quote more than one figure a "highway" and "urban", but presumably the rest are just everyone's average? If so, my average over the last 2500 miles has been 42.9 (econometer), and a real (brimmed tanks) 40.7. Unfortunately, without knowing my mix of urban and motorway miles, that's actually pretty meaningless.

The manufacturers' official figures are not usually that representative of real life because they're done under strictly controlled lab conditions to a drive cycle that isn't necessarily that representative of real-life use. It's probably pretty representative of how a small-ish hatchback might get used, but totally unrepresentative of how a Ferrari would get used. I've always thought that the drive cycle should include a percentage of full power operation rather than a particular range of speeds and accelerations, because otherwise, the little city cars are pretty much "foot-to-the-boards" trying to follow the prescribed cycle whilst the Ferrari can do it on an almost closed throttle.

Unfortunately, I don't see that spreadsheet as any better (but for different reasons). It's going to include all sorts of innacuracies arising from the particular conditions of use - e.g. the same make and model of big 4x4 could have two entries - one for the school run mum who uses it under near-ideal conditions, the other for the road maintenance bloke who habitually tows a trailer with a mini digger on it in urban conditions. It will include simple arithmetical errors (like the 43000 MPG for a Micra)! It will also include the personal fantasies of particular owners (like the ones who really seem to believe their cars are more economical at 80 than at 60!), and it doesn't seem to quote the mileage of each vehicle, so we have no idea about how many miles it has done or how it has been maintained. There are also (despite there being 3000 entries) precious few for the same make, year and model of vehicle. In fact, some of the model descriptions were almost non-existant. I did notice three identical figures for the same make and model of VW, but they all seemed to have been entered within a few seconds of each other so I assume they were just duplicate entries.

Seriously, try the "averaged econometer" test - you've nothing to loose! Sure, I can accept that it won't be 100% accurate (few of them are) but you're only using it as a comparator - is it more or less economical at speed A than at Speed B? The actual number you get may well be a few MPG wrong, but all you're looking for is whether it goes up or down. You can always (if you have the time, space and inclination) always verify it by actually driving at those speeds constantly and topping up with a Jerry can. My own "real world" figures (over many 10s of thousands of miles in at least a dozen different modern diesel cars) all point to the same thing. They're most economical at such low speeds as to make them near-useless as a means of transport!

Haven't got an "econometer", and wouldn't pay it much attention if I did....I like to get home in one piece and the only thing that gets much of a look-at is the speedo....I don't "do" radios' or cds' either.
Got a nice BRIGHT light when the fuel hits 10 litres remaining.
Gotta go a few hundred miles...I zero the odo and go....the fuel gauge is exceptional....empty is nothing left, quarter is 22 litres....half is 44 litres....note fuel in, note fuel bought, note fuel remaining. Quite accurate over time and distance.
Mostly small trips, so they get noted. Fuel receipts kept (of course)...
Over time it is accurate.
The manu figures are those given in the user manual.....over time I have come to recognise they are right...they are not the industry/government twaddle (extra-urban tosh indeed).
It works for me....nearly 200 miles to fakenham and back = nearly 40 litres. Figures I can bank on....couldn't give a rats backside about the government, who are basically a load of thieves.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

When electric vehicles become more commonplace I imagine the so-called sweet spot will cease to be a factor because, AFAIK and from personal experience, the complete engine range is a sweet spot in all electric engines.

In which case it will be down quite simply to slower is more economical because the only other main factor will be the aerodynamics. And that, no matter how aerodynamic the vehicle, will only create more resistance the faster you go from zero mph.

Makes you wonder where it’s all leading... And that exercise is good for us. It's nice to know the Gov loves and cares for us all isn't it?

"Why does a Government think it owns my life?" (T. Pratchett)

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

I wouldn't bet my life on electrically-propelled vehicles being that commonplace.
I do not count as "electrically-propelled" vehicles where a generator is driven by an on-board internal combustion engine.
Battery technology is hardly forging ahead and providing us with cheap, easy and safe electrical storage.
Instead we seem to be faced with a multitude of ways of generating electricity as we move.
Charging overnight is hardly going to be cheap if prices keep going up, which the government seems to insist they must, even if only to force people to use less so as to meet emission reductions.
Shale gas/oil seems stalled/bogged-down not only in the UK, but in europe, where some countries have just refused it.
I see the problems as being......
Companies, at the behest of government, keeping prices high no matter what.
As more battery/electric vehicles arrive their cost of operating is going to increase with the source of their charging increasing in price by some 10%/yr. When they reach a magical number, the cost of electricity will be higher, and it is by no means guaranteed that the cost of vehicle charging will be the same as that for household power (taking into account the push towards so-called smart meters and other means of limiting domestic usage.
At the moment their taxation is minimal, that will not be the case if widespread usage happens.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

That's precisely it Tone. The opposition to movement comes from rolling resistance (more or less constant regardless of speed), wind resistance (goes up with the square of the speed) and (if accelerating or climbing a hill) the weight. Slower is always better when it comes to electric vehicle range. As modern diesels creep closer to the sort of efficiency that electric moors can manage (still some way off though!) the same thing happens and you end up with fewer "sweet spots" and a general "slower-is-better" situation.

The rest of the car industry is betting on a pretty rapid rise in EVs in the next 5 years. Personally, I don't think it will happen as quickly as the industry thinks it will, but I do think they're be pretty common as second cars in (say) 10 years time.

It's advancing faster than any of the conventional IC engine technologies. I reckon we'll see one order of magnitude improvement in energy density within 5 years. We're not going to see any "order of magnitude" improvments in conventional vehicles in that time!

They can go up a long way before they catch conventional fuel up! Currently we're getting about 100 miles for about £2 using overnight charging. That's for Transit-sized vehicles.

Hasn't happened with LPG though, has it? I agree that if EVs become very popular, the government won't be able to afford to loose the revenue and will, I'm sure, whack the tax take up. That said, we're a long way off that just yet. Besides, the nice thing about electricity is that unlike petrol and diesel, the general public have the ability to generate small amounts of it independently.

To my mind, the biggest current problem with EVs is the eye-watering cost of the batteries and the fact that they are likely to loose range with time. By the time the battery is 6-7 years old, it will be significantly down on range and the owner is unlikely to want to spend more than the car is worth on a replacement battery. There's no equivalent expenditure that becomes necessary on a conventional car about half way through it's life so we end up with the self-fulfilling prophecy in that as news gets round that they're likely to need a new battery at that sort of age, the cars' residual values will plummet (like buying a house 96 years into its 99 year lease)! This in trun, will make the owner even less likely to cash out for a new battery. Many EV suppliers lease the batteries for this (and other) reasons, but of course you're then still forking out a regular sum to underwrite the battery depreciation.

The industry is betting on a rise in the number, based upon a rise in the available subsidy from government/s.
Not forgetting that a government subsidy towards those owning these expensive and short-lived vehicles is paid by all, most of who will never own one because they are unlikely to be a used-car option.

Batteries. Inevitably lithium-ion. Life-time limited, as are all batteries.
But with major problems. Strictly regulated charging is necessary. The life of the cells is shorter, sometimes much shorter, as the current drawn from them increases. Regular use at high discharge rates shortens cell life dramatically.
Largely unreported problems also exist in below-threshold discharge, at which time safety devices contained within the cell will operate and render it useless (ie: not usable anymore.) So parking it in the garage and departing on holiday will cause problems if not charged before departure.

Lpg in cars is still a minority use.
Also largely unreported, with respect to lpg, is that in many makes of car there are problems with valve life.
I've seen cars run on lpg where the valves have receded to the point where they ceased to be valves and became an obstruction in the exhaust port.
Solvable by installing hardened valves and seats. High cost.

Everything has its down side.

Fortunately I will not be around to see wide-scale use of solely-battery-powered electric vehicles.

So with only a forecast sale figure of 7% of total car sales by 2020, electric vehicles (all types, not solely battery) are not going to set the world on fire (although they seem to have that problem themselves)

And even then only by the poors taxes subsidising the rich in their 'leccy cars.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

The problem with EV's is to my mind one of concept. Manufacturers are spending a fortune trying to make a practical "One size fits all" alternative to ICE vehicles. I really dont think it is going to happen! And it doesnt have to!

An EV with a range of 30 miles and a top speed of 30-40MPH is just fine-as a second or even third vehicle! this is easily achievable with (relativly) low cost lead/acid technology!

A vehicle like this would probabally be suitable for 80-90% of my "Social Domestic and pleasure" journeys and about 50% of my total SDP annual milage. I dont imagine that my SDP requirements are that different to most!

A EV and a Landcruiser Amazon would comfortably meet all my needs! (Indeed, I am surprised that the likes of Toyota do not market a "Package deal" combining a landcruiser with an EV It would be good publicity IMO)

All I need now is the EV ! . Maybe I should build one!

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"The road to a police state is paved with public safety legislation"

Last item by Dusty ,made me think of how many disabled cars are in town nowadays since a lot of the bays are now disabled only. It would be interesting to see how many disabled manage to clock up a lot of miles .Especially if it's a mobility vehicle ,where the allowance is used to pay for it ,leaving what to pay for fuel.Might be a nice little niche market for EVs ?

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

This from a "electric car buyers guide" [sic]



Several minor problems.
No, no renewable "power stations".
Too unreliable, never generating when needed.
Not a "hub and spokes" system now.
Any system using renewable sources that we have now is going to be unreliable and prone to almost daily outages.
For every MW of renewable generation there is a MW of fossil/nuclear backing it up.
Seems the present government is seeing the writing on the wall and dumping land-based wind and solar rather rapidly, off-shore will go soon....or remain as an expensive beach offshore-eyesore.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

I am convinced that 80mph is so slow that anyone even my 90 year old gran can manage to operate a car under motorway conditions in perfect safety at that and higher speeds. Closing speeds are on M-ways are low, hazards easy to spot and that is where the issues lie on other types of road.

The numbers you are using are the result of a succesful brainwashing exercise, 70 was plucked out of thin air based on the fact that most cars when it was 'chosen' could not really sustain that speed. If we repeated the same scientific excercise now the UK speed limit would be 130 mph....

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Enjoying the twilight years of personal freedom in the UK (and my M3) :)

I remain underconvinced.
Closing speeds are slow. No. The collision speed may be slower than for head-on between vehicles travelling in opposite directions, but any collision speed is magnified by the other vehicles that pile into the wreckage. Add a truck or two and things get very messy, very fast.
People do not change, never mind how much you improve the engineering the person is not changed. First the driver has to recognise there is a problem ahead, then he/she has to produce the correct reaction to the developing situation ahead in time to avoid the initial problem while ALSO not making OTHER problems for other drivers by his/her avoidance reaction.
Now, not mentioned very often is the problem of trucks...which, unlike cars, tend to go THROUGH the central reservation barriers. Very messy, very fast.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

I find an indicated 80mph, actual 75mph, is fast enough to feel I’m getting somewhere but slow enough to still get a good range from a tank full. When I was in Germany cruising at between 130 to 140mph on my way to Luxembourg I was shocked at the exponential petrol drain. As James May put it well referring to high speeds as he tried for a top speed in a Buggati - it’s like trying to push through mud the faster you go.

So when I was over there I decided a true 80mph was enough; for all the right reasons. In fact I wouldn’t be surprised if any modern day car wouldn’t return better mpg at 80mph than my old Morris Marina 1800 used to do at the oft quoted 55mph.

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

Sorry, I don't agree with that at all, some people show a remarkable ability to completely ignore warning signs of trouble ahead and carry on at their chosen cruising speed regardless of very clear indications that there is definitely a problem looming.

I once (loooong time ago now) recovered a broken down car from the centre lane of the M74, boy that was an eye opener There was a marked police traffic car parked back up the motorway with blue lights going and two uniformed traffic officers waving traffic down, me at the breakdown site with fluorescent orange and white truck with amber beacons going, a car stationary in the centre lane, and brake lights coming on all over the place, plenty of indication that something was up one would have thought? ....Ummmm that would be no .... Quite a few vehicles arrived at the site without slowing noticeably at all, then had to take emergency evasive action to avoid ploughing into the broken down car, or another vehicle which was taking evasive action. There were several sets of black lines from locked wheels left on the road, violent braking/swerving manouvers with loss of control, some of the "violent swervers" clearly had no idea if the lane they were swerving into was free of approaching traffic coming from behind.

Mayhem .... IMO there were no collisions due to the folks that did do something about it early and stayed out of the way of the "what problem?" ppl, and luck. IMO some people can't manage to operate a car under motorway conditions in anything like perfect safety at all ever!! It has nowt to do with speed, much to to with proper observation and taking effective early action on those observations. Motorways might be "the safest roads" but IMO that is not because ppl drive well on them.

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You only need two tools - WD40 and duct tape. If it doesn't move and it should, use WD40. If it moves and it shouldn't, use duct tape. :0)

Probably not so much always being unaware of what’s ahead outside the car IMO Zipps and more to do with f n’ about with something in the car.

I see it all the time

None so blind as those who aren't looking at what they should be looking at. Nuff said...

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.