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vic

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Dizzy, so what if cyclists have cars? They should pay tax...... just because they should.

 

They are a danger and pose more of a threat than any car with their weaving and dodging red lights..... they are only a step away however, from motorcyclists who do all of the above and can do it at 150mph!! ............but at least they pay tax, regardless of how little CO2 they pump out and regardless of whether the owner has a car and already pays tax like that!

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Hi

 

Some observations.

 

There are no plans for a "blanket" imposition of 20mph speed limits, only a "default". Traffic authorities are free to decide where a road should have a higher limits and have justifiable reasons for doing so.

 

I have already posted the links to reports on fuel consumption which no-one ever seems to read. For the record, here they are again :-

 

1) Report on 30kph in Belgium

 

http://www.20splentyforus.org.uk/UsefulReports/Impact%20of%2030%20kmh%20zone%20i.pdf

 

Results indicate that emissions of most classic pollutants should not be expected to rise or fall dramatically. Nevertheless VeTESS results indicate that some emissions such as PM exhaust from diesels may show a significant decrease, whereas MEET functions assume a moderate increase. Exposure of residents to one of the most toxic components of the urban air pollution mixture may therefore also decrease.

 

2) Times article on research by

 

http://www.timesonline.co.uk/tol/driving/article4107764.ece

 

The study, by Peter De Nayer, a former AA fuel efficiency expert, involved fitting cars with a fuel flow meter and testing them at Millbrook proving ground in Bedfordshire. He found that a Citro?n C4 1.6 diesel achieved 99.6mpg at 20mph but only 29.3mpg at 90mph.

 

But the study, commissioned by What Car? magazine and based on five cars of different sizes ranging from a 1 litre Toyota Aygo to a 2.2 litre Land Rover Freelander, found that the most efficient speed was below 40mph for all five and as low as 20mph for two.

 

 

You should also be aware that limiting the speed to 20mph eliminates all acceleration from 20mph to 30mph. As it is acceleration that uses fuel far more than a steady speed then this reduces consumption significantly. Lower speed limits create smoother driving which in turn reduces fuel consumption.

 

Other organisations who seem happy with the "green" credentials of lower speeds include DfT, Sustainable Development Commission, Green Party, to name a few.

 

 

Best regards

 

 

Rod

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MY apologies to Dizzy. I had not seen her reference to the Times article.

 

In fact the original What Car article said that the difference between a "steady" 20mph and 30mph was 10%. It was equally split between cars which were 10% more efficient at 20mph and those more efficient at 30mph. It will all depend on the exact gear ratios and the torque and fuel consumption curve of the engine.

 

In any case throughout Northern Europe the same cars are being used with an 18.6 mph speed limit.

 

I trust that this helps. The fuel consumption/emissions issue can be debated ad-infinitum between those who believe that driving slower and more calmly reduces consumption/emmission and those who insist that higher speeds should be maintained.

 

And of course where people decide to switch to walking or cycling then their fuel consumption drops completely.

 

I am aware that someone keeps on wanting to tax cyclists, and perhaps even walkers. But do this on the same emission rates as motor vehciles and their annual payment would be zero. Hence it is completely completely irrelevent to the debate on lower speeds.

 

Best regards

 

rod

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1) Report on 30kph in Belgium

 

Results indicate that emissions of most classic pollutants should not be expected to rise or fall dramatically.

 

So, no measurable benefit then.

 

 

2) Times article on research by

 

The study, by Peter De Nayer, a former AA fuel efficiency expert, involved fitting cars with a fuel flow meter and testing them at Millbrook proving ground in Bedfordshire. He found that a Citro?n C4 1.6 diesel achieved 99.6mpg at 20mph but only 29.3mpg at 90mph.

 

Of course a car is more fuel efficient at 20mph than it is at 90mph, but that study says nothing about the relative efficiencies at 20mph vs 30mph - and so is completely irrelevent to your argument.

 

But the study, commissioned by What Car? magazine and based on five cars of different sizes ranging from a 1 litre Toyota Aygo to a 2.2 litre Land Rover Freelander, found that the most efficient speed was below 40mph for all five and as low as 20mph for two.

 

In other words - well over half of the cars tested were more fuel efficient at above the maximum speed limit you advocate. Kind of proves what almost everyone who's commented has been asserting, doesn't it?

 

You should also be aware that limiting the speed to 20mph eliminates all acceleration from 20mph to 30mph.

 

Poppycock! A driver would have to brake from a higher speed when entering a 20mph limit - thus wasting fuel - and accelerate again from 20mph to 30mph when leaving it.

 

Lower speed limits create smoother driving which in turn reduces fuel consumption.

 

No they don't. They increase driver frustration and will tend to encourage HARDER acceleration and later braking as drivers will want to reach their maximum speed more quickly in an attempt to claw back some of the extra journey time the new, lower limit is costing them.

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ahhh yes, the Green party.... not quite as popular as the BNP as I recall?

 

The Sustainable Development Commission, a government funded; but supposedly independant quango which is facing the chop and the good old Department for Transport..... another government department flushed with its past successes!

 

I did have a read on the DFT website and found a document by some outfit called "cycling England"..... it was a 3 page recommendation document of what they WANT when it comes to cyclists and roads and stuff.......

 

check out this nonsense.....

 

http://www.dft.gov.uk/cyclingengland/site/wp-content/uploads/2009/10/cycling-england-advice-note-development-v04-0910.pdf

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The study, by Peter De Nayer, a former AA fuel efficiency expert, involved fitting cars with a fuel flow meter and testing them at Millbrook proving ground in Bedfordshire. He found that a Citro?n C4 1.6 diesel achieved 99.6mpg at 20mph but only 29.3mpg at 90mph.

 

But the study, commissioned by What Car? magazine and based on five cars of different sizes ranging from a 1 litre Toyota Aygo to a 2.2 litre Land Rover Freelander, found that the most efficient speed was below 40mph for all five and as low as 20mph for two.

As inky has so clearly pointed out above, this actually DIPROVES your argument, and upholds ours. :roll:
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And of course where people decide to switch to walking or cycling then their fuel consumption drops completely.

 

rod

 

 

ooh a bit patronising isnt it? Why on earth would anyone want to walk or cycle when it is bucketing down?

 

I am aware that someone keeps on wanting to tax cyclists, and perhaps even walkers. But do this on the same emission rates as motor vehciles and their annual payment would be zero. Hence it is completely completely irrelevent to the debate on lower speeds.

rod

 

hmmm that'll be me then. Rod, even motorcycles pay road tax, the cars which pay no road tax still pay tax and VAT on the fuel they use, on the MOT they have to endure to ensure they are safe to go on the highways (remind me again, do cycles have to have their brakes and things checked to see if they are safe?)

 

so my arguement to make cyclists pay some form of tax to use the road is far from irrelevent .

 

Plus, a blanket ban should be brought in to stop flabby cyclists from wearing lycra...... eeewwww.....

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SL

In the Netherlands where they do this they have a 30kph speed limit and strict liability regarding pedestrians and cyclists.

 

Are you advocating these?

 

Rod

What about your research documents quoted above Rod? I take it your lack of response is an admission that they don't prove what you claimed they were proving?
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What about your research documents quoted above Rod? I take it your lack of response is an admission that they don't prove what you claimed they were proving?

 

 

sssshhh don't mention that FS..... he was hoping nobody had noticed! :lol:

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Fatshaft

 

My lack of response is due to being otherwise engaged with a local authority in the Northeast who is planning a Total 20 implementation.

 

Another group of councillors who are keen to make their town a better place to live.

 

But as this seems to be descending into an anti-cycling thread then I thought I would let things cool down.

 

You know as well as I that accelerating used fuel and the fact that your car may use slightly more fuel at 20 mph is of little relevance.

 

Best regards and be happy

 

Rod

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Hi Rod... it is starting to sound a bit like a witch hunt (or should I say 'warlock' hunt) eh.

 

Can I ask which Northeast LA is planning on implementing the 'Total 20' plan ?

 

Maybe we should all go back to the beginning as we seem stuck in a rut over the disagreement re pollution/fuel/revs etc. :shock:

 

So What WAS the original main objective re the possible implementation of a 20 mph speed limit :oops::?

 

Was polution/noise/fuel consumption etc a consideration in the first place or have these just been brought in as a side arguement in favour of the reduction?

 

Was the original objective just to somehow reduce the number of pedestrians killed or injured by being hit by cars ?

 

I for one am starting to lose all focus on what it's all really about mainly because these other faltering statistics and reasonings are completely clouding the issue :oops:

 

I don't hate cyclists by the way Rod although my car still definately doesn't like travelling at a constant 20 mph :wink:

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Seems to me that the only person who was concerned enough about this matter, which affected him or his, found the gumption to get off his backside and try to change things and actually achieved at least some if not all of his aims. Its all well and good whinging and moaning into the ether but unless you can be bothered to follow it through with REAL effort and REAL action its just hot air and hyperbole.

Frankly I am not certain where I stand regarding the complex pros and cons of this issue but having seen a child hit by a car doing around 30mph I truly feel that anything which can save just 1 of these accidents from occuring is worth a few minutes of my time.

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I agree PJ but the emphasis on the 20's plenty campaign and it's strategy seems to have completely gone away from the issue of kids being killed on the roads.

 

I'm still not convinced however that a total 20 mph roll out is the way forward (agree with it on certain roads) but kids will still be as oblivious to cars and the need for taking responsibility for their own actions and safety such as 'stopping, looking and listening' like we were always taught.

 

Yes their survival rate might be higher if they are hit at 20 rather than 30... but they will still be hit if they just walk out in front of a car :shock:

 

The responsibility now seems to be purely on the heads of the drivers rather than the pedestrians too. Road safety is surely a two way thing :?

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Yes it does.. being hit by a car when you are chatting to your mates or listening to your ipod while texting on your mobile will HURT regardless of what speed the car is going... although it may not actually kill you :roll:

 

You can get knocked over or knocked off your push bike at 10mph and still suffer severe injury or brain damage as your head hits the floor :?

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Ok dont slow the traffic teach the children dodge car.

 

Me driving at 20 instead of 30 will never, never, never, increase the chances of me hitting a child on the road.

 

For pitys sake if anyone can do more than 20 in this town at rush hours they are doing really well.

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I firmly believe that slowing to 20 will increase the potential for accidents because the pedestrians will take more risks thinking that cars will be slower thus giving them time to dash across the road.

it happens at 30, so it's definitely going to happen at 20.

Also, being hit by a car at any speed is dangerous, can break bones and even kill if hit in the right place.

And when you have drivers texting and using their mobiles at 30 plus, what will they be doing at 20? Reading War and Peace?

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Whatever limit is set, there?ll always be accidents and calls for even lower limits, it could go on forever like this thread.

 

The present limits are reasonable and educating the kids should be the first step rather than telling them the roads are safer.

 

Bill :)

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