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I did the same thing myself yesterday, only I was looking at my instantaneous fuel consumption instead of my revs.

 

At 30mph in 4th I was getting around 15% better fuel miles per gallon than at 20mph in 2nd, and about 10% better than 20mph in 3rd (although the engine was struggling so badly I had to keep changing back down into 2nd for even the slightest incline).

 

Ain't facts inconvenient when you're on a crusade?

 

:lol::lol::lol:

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http://www.20splentyforus.org.uk/BriefingSheets/pollutionbriefing.pdf

 

ps and apparently the reduction in noise and pollution would occur because less people would drive and more people would walk and use bikes if the speed limit was reduced to 20mph... so nothing to do with me, my car, my lack of phsysics understanding or my driving skills :lol::wink:

 

No, it says that essentially it makes little difference (and transfer to other modes is an additional benefit). The scientific paper is at http://www.vito.be/VITO/OpenWoDocument.aspx?wovitoguid=6CED3657-6F79-45A3-BCD7-AE34DA74BA4D

and says some diesel particles show a significant decrease.

 

Most cars will trundle happily in 3rd at 20. Yes, you'd use less fuel at 30 in 4th, but you have to use more fuel to get to 4th.

 

It wouldn't be the only counter-intuitive thing in transport research. Try the Braess paradox where closing off a road can speed up traffic... http://en.wikipedia.org/wiki/Braess%27s_paradox

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can't say that i have a problem with changing up and down the gears.

 

mind you i do drive a motor that has a belt drive and is a CVT automatic so it is just a matter of how far i have to depress the accele.. acelle.. go faster pedal :lol:

 

when on the bike however i find that trying to maintain 20 mph in fifth results in an engine speed that is just short of stalling. (and makes for a rather jerky ride as any slight movement of the throttle makes the bike either leap forward or dive as the revs drop) so it is a matter of constantly juggling between second and third.

 

now then after reading the last few posts, how many of you would have had the time to monitor the various things had you been travelling at thirty?

 

also if you had had an accident could you have been done for driving without due care and attention?

 

travelling at 20 are you more distracted than when you travel at 30 ?

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[Most cars will trundle happily in 3rd at 20. Yes, you'd use less fuel at 30 in 4th, but you have to use more fuel to get to 4th.

 

 

So the ideal would be to keep traffic moving smoothly at 30mph and not constantly force it to speed up and slow down with traffic lights on roundabouts, buses pulling out of bus lanes to overtake, and un-necessary and arbitrary changes in speed limits.

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I bet the 20's plenty lot hate this Forum. :lol:

 

Maybe we need a "30 is safer" group, or a "look where you are going" group? :wink:

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We've only just had millions spent on a government (and RoSPA) sponsored "it's 30 for a reason" campaign.

 

If the "20's Plenty" brigade would have us believe that all of the experts involved in the research behind that conclusion were wrong - then how can we give their own mathematically challenged "experts" any more credence?

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Tried it and our automatic 3.0L car changes to 2nd gear at around 15mph and will just about change to 3rd at 20 as long as I put my foot down for a sec to boost speed/revs... otherwise it seems to want to stay in 2nd all the time. IT IS DEFINATELY NOISIER !!

 

Not tried it on the other car yet which isn't automatic and is only a 1.6.

 

I suppose though that all this is slightly irellevant if only a few short roads are changed to 20mph but is IS relevant if there is a blanket rollout on all roads in the area :wink:

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Especially if they are big ones eh :lol::wink:

 

Might use more fuel and weighing 2 tons that is expected but that's not the point I was making.... it struggles to get into 3rd gear driving at a constant 20 mph :P

 

So therefore it must be using even more fuel that it usually guzzles :lol:

 

Can't believe that a certain person hasn't been back on fighting from the other corner and telling me off for having a fuel guzzling, planet destroying, people crushing, cyclist wobbler of a vehicle. It's got bull bars on the front too but that's so cyclists and kids can grab hold and cruise with me after I clip them :lol:

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I hope we haven't offended him as he keeps coming on but going again without word. :shock:

 

Rod.. if your still reading I didn't mean to offend I'm just trying to figure it all out as the stats and reasoning still don't make any sense to me at all... hence all my questions and 'disagreement' chat :oops::D It's what us women are like :wink:

 

Baz and the other blokes have no such excuse :lol:

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I don't need excuses Diz. When someone comes onto the forum at complete odds with everyone else?s viewpoint, they're going to end up getting some flack and with the best will in the world it's going to appear personal. :shock:

 

When this all started out I used to agree with a lot Rods logic but these days, like most people here, I find myself completely at odds with pretty much most of what he says and I have to wonder if this crusade has had some kind of detrimental effect on his mental state.

 

This state of mind thought came to mind recently when Geoff Settle joined the debate on news page replies section in support of Rods plans. Now Geoff's a nice bloke but his posting here often made me wonder if he was living on the same planet, after all he's the only person in Warrington that can walk down Winwick Street and say what a truly wonderful job the council have made of the area. :lol::lol::lol:

 

The worry for me now is that with people like Geoff involved in the decision making process, then before long we wont have to worry about reduced speed limits because we'll all be jogging and cycling everywhere while discussing flowers and water voles. :lol:

 

Bill :)

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Dizzy,

 

my stance is just slightly right of Jeremy Clarkson. Car divers pay bucket loads of tax and so should have the priority. Footpaths for pedestrians crossings to get them from one side of the road to the other and a few white painted lines as a consession to the cycling nazis

 

As for the rest of it; 20's nonsense on main arterial roads regardless of whatever statistics the lycra brigade want to push out..... until the oil runs out, cars are here to stay..... and the bigger the better :wink:

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I believe that the majority of the general public would prefer to see reduced limits rather than other forms of traffic calming measures such as speed bumps, particularly where roads in question merit concern but Rods blanket approach just goes too far.

 

Bill :)

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Well I'm not jogging anywhere for anyone Bill and flowers make me sneeze although I do think watervoles are rather cute though :lol:

 

The 20's discussion seems to still be going on under the news page article and there is an interesting link posted by Mr King on there in response to 'Rolfman'.... a question relating to the belief of the experts findings is also posed to Fatshaft a few times too.

 

Rod King said this on 22 Oct 2010 8:18:41 PM BST

Hi Here is an article that shows that on balance 20mph is not very diifferent from 30mph in fuel consumption. http://www.timesonline.co.uk/tol/driving/article4107764.ece

 

Interesting although when I have read it there seems to be no direct reference to specify that 'on balance driving at 20 is not very different that driving at 30 in terms of fuel consumption ?'

 

It has comparisons against other speeds but nothing mentioned or conclusive about the 30 vs 20 dilemma !! (I have of course asked the question under the news article). So why is this now being used as an arguement in favour of no difference in fuel consumption at 20 mph to 30 mph ?? :?

 

Maybe I have just missed it :?

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oooh I must type slow as the other two comments weren't there when I started typing.

 

Bill... yes I'd rather see reduced speed on roads with concern or obvious dangers than speed bumps although people tend to take more notice of the bumps than the signs. The blanket 20mph approach across all roads though I strongly disagree with.

 

Baz... I have no problem sharing the roads with cyclists (well apart from the idiot ones of course) and I don't even have an issue about the fact that we pay car tax and some possibly don't as most cyclists probably have cars too so pay their dues anyway. I could cycle if I wanted too... I just don't want to.... I don't like it... and it's not convenient for me.

 

I don't have an issue with pedestrians either as I am one of those too... but I also drive a car... as walking is not always convenient.

 

It's all about choice and yes big cars are better unless you are comparing them with bright orange lamborghinis :D:wink:

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read the article an now have a great excuse for causing mayhem on the motorway. :twisted::twisted:

 

get on the inside lane and tootle along at twenty mph. if pulled over just quote the article saying that it is more fuel efficient at twenty and that i am saving fuel and thus the environment. the fact that there are two hundred irate motorists behind me ready to form a lynch mob is irrelevant. :wink:

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Inky Pete said

So the ideal would be to keep traffic moving smoothly at 30mph and not constantly force it to speed up and slow down with traffic lights on roundabouts, buses pulling out of bus lanes to overtake, and un-necessary and arbitrary changes in speed limits.

 

 

I thought this was what "traffic management" was supposed to do.

I think WBC have lost sight of this as have the councillors who decided to continue with the waste of money scheme.

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