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If you don't vote for "any of them" Wahl; how will you decide who is in power? :?

 

What is the minimum number of votes needed to get elected if the majority didn't vote?

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Is anyone good a physics.... this is frustrating me now after and I'm adamant that my car is no louder at 30 mph than it is at 20.

 

Dizzy... If your car is as quiet at 30mph as at 20mph then it would appear to be defying the laws of physics!
one of the many comment points under the news page article

 

So is it just my ears and do I need to apologise to Rod :oops::lol:

 

Also I recon that driving at a continuous slower speed will increase pollution (rather than lower it as is the claim) as lower gears would be used hence higher revs, increased fuel conumption and therefore higher engine emissions?

 

So again am I wrong and do I need to apologise

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Is anyone good a physics.... this is frustrating me now after and I'm adamant that my car is no louder at 30 mph than it is at 20.

 

Dizzy... If your car is as quiet at 30mph as at 20mph then it would appear to be defying the laws of physics!
one of the many comment points under the news page article

 

So is it just my ears and do I need to apologise to Rod :oops::lol:

 

Also I recon that driving at a continuous slower speed will increase pollution (rather than lower it as is the claim) as lower gears would be used hence higher revs, increased fuel conumption and therefore higher engine emissions?

 

So again am I wrong and do I need to apologise

 

I agree with you.

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................but Dizzy..... Rod is NEVER wrong! How dare you question him!! :lol:

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Is anyone good a physics.... this is frustrating me now after and I'm adamant that my car is no louder at 30 mph than it is at 20.

 

Dizzy... If your car is as quiet at 30mph as at 20mph then it would appear to be defying the laws of physics!
one of the many comment points under the news page article

 

So is it just my ears and do I need to apologise to Rod :oops::lol:

 

Also I recon that driving at a continuous slower speed will increase pollution (rather than lower it as is the claim) as lower gears would be used hence higher revs, increased fuel conumption and therefore higher engine emissions?

 

So again am I wrong and do I need to apologise

 

I agree with you.

You're bob on Dizzy. We had this out with Rod the last time he showed his face, I tried expalining that his pollution argument was balls, driving at 20mph involves higher revs in a lower gear than 30mph does, and that was before he's now gone down the noise route as well.

 

The guy is clearly bonkers if he doesn't realise this.

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So no need for me to apologise then for my 'stupidity'... phew :shock::lol:

 

Surely all these ridiculous statments and factless facts that are being put forward in favour of the idea aren't helping in the slightest... infact it's what's put me off taking any of it seriously at all now :roll:

 

Bonkers :oops: Sorry Rod if you are reading :?

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As understand it, it is the manner in which you are driving, at whatever speed, that is more important. If you can maintain a smooth journey by anticipating the conditions and speed necessary, choosing the correct gear for the speed you are going, that will help with the fuel efficiency.

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I'm afraid you understand wrong SL.

 

A car engine produces power over a limited proportion of its rev range.

 

At 30mph the vast majority of cars will be in 4th gear at the bottom end of the power range of the engine.

 

At 20mph the engine will be revving far too slowly in 4th gear to produce any power - and will be in danger of stalling. The driver will have to change down into 3rd gear, or possibly even 2nd, in order to keep going. This will then cause the engine to be revving MORE quickly and MORE loudly than it was at 30mph in 4th gear.

 

Add in the fact that a journey observing 20mph limits will ALWAYS take longer than one observing 30mph limits, and all of a sudden you've used MORE fuel on your journey by going slower.

 

Cars engine power bands and gear ratios are specifically designed to deliver best fuel economy at the speeds the manufacturers anticipate the car to spend most of it's time travelling at. Namely, our ones.

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Another point to consider with a top 20mph speed limit is that it would be highly unlikely for any driver/car to actually manage to get into 4th or 5th gear anyway :? Not good in my opinion especially if all roads round here were reduced.

 

I'm not entirely sure at what speed I change gear at as I do it without thinking so will 'evaluate fully' tomorrow but I'm sure it must be somewhere near to 20mph that I go from 2nd to 3rd.

 

.... anway the pollution and fuel saving side of it all is 'explained' here

 

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

 

http://www.20splentyforus.org.uk/Documents/LA_FAQ.pdfand'>http://www.20splentyforus.org.uk/Documents/LA_FAQ.pdfand here

 

and somewhere else... may have been here

 

http://www.20splentyforus.org.uk/Documents/LA_FAQ.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:

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At 30mph the vast majority of cars will be in 4th gear at the bottom end of the power range of the engine.

 

At 20mph the engine will be revving far too slowly in 4th gear to produce any power - and will be in danger of stalling. The driver will have to change down into 3rd gear, or possibly even 2nd, in order to keep going. This will then cause the engine to be revving MORE quickly and MORE loudly than it was at 30mph in 4th gear.

 

I would NEVER drive at 20mph in 4th gear, I would already be in second - correct use of the gears and gear changes DOES result in fuel saving.

 

You also assume that the whole journey would be at 20mph, which is not most people's experience, only for a short part of their journey. If someone was doing any number of journeys that were always at 20mph and no faster, it would make more sense to walk!!! :roll:

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Dizzy, your last para will be why the council are supporting it. they need more on the buses to make some money. :wink:

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SL driving along a whole road/or roads at 20 in 2nd gear will definately use more fuel.

 

If you are only driving around Warrington the whole journey 'could' be 20 mph if the blanket rollout is approved.

 

and yes it would make more sense to walk... which is what the cyclists and 20's plenty group would prefer :wink:

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Except if you walk, you are more likely to be run over by the idiot cyclists riding on the footpaths..... of which there could be an increase!! :lol:

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At 30mph the vast majority of cars will be in 4th gear at the bottom end of the power range of the engine.

 

At 20mph the engine will be revving far too slowly in 4th gear to produce any power - and will be in danger of stalling. The driver will have to change down into 3rd gear, or possibly even 2nd, in order to keep going. This will then cause the engine to be revving MORE quickly and MORE loudly than it was at 30mph in 4th gear.

 

I would NEVER drive at 20mph in 4th gear, I would already be in second - correct use of the gears and gear changes DOES result in fuel saving.

 

You also assume that the whole journey would be at 20mph, which is not most people's experience, only for a short part of their journey. If someone was doing any number of journeys that were always at 20mph and no faster, it would make more sense to walk!!! :roll:

Sorry SL, but as it has already been explained to you, this is plain wrong. Yes if you accelerate slowly, change up quickly, you will use less fuel than if you accelerate like Jenson Button, and hit the red line before changing up.

 

That's a different argument entirely. If you were to drive anywhere in second or third gear, then repeat the same journey while in fourth or fifth gear, you would use much less fuel by being in top gear. You would also be creating less noise as your revs would be lower, and it's the revving of the engine that makes the noise.

 

Much as Rod tries to spout his lies, physics I'm afraid is 100% against him.

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Think fuel saving has more to do with rpm than mph? :?

 

Yep which is what we were saying..... did you miss a bit :lol:

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....and if you try to drive very slowly - for example at 20mph - you are forced by the way the car engine and its gearbox are designed to use a lower gear and relatively higher revs.

 

Added to the increased journey time, this means that a car is significantly LESS efficient driven at a maximum of 20mph than if driven with the same driving style on the same journey under a speed limit of 30mph.

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Apparently, even the Autobahns are running slow nowadays. Most of them are only 2 lanes wide and they suffer from the same problem as us of 2 lorries side by side travelling at almost exactly the same speed.

 

They call this the Elefantenrennen - or Elephant Race.

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Well I tried 20mph: in 4th = 1500rpm: in 3rd = 2000rpm: in 2nd = 2500rpm. The problem is, you have to keep changing down to less than 5mph to avoid the road humps wrecking your suspension. :roll:

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Well I tried 20mph: in 4th = 1500rpm: in 3rd = 2000rpm: in 2nd = 2500rpm. The problem is, you have to keep changing down to less than 5mph to avoid the road humps wrecking your suspension. :roll:
Funnily enough, becasue of thius thread I did the same yesterday morning.

 

I'm afraid like has been said, 20 is not plenty in 4th for me, so I had to change down.

 

20mph in second - 1800rpm

30mph in 4th - 1500 rpm

40mph in 6th - 1500 rpm

 

I don't expect to see Rod King and his pseudo science making an appearance to refute this tho.

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