20mph Speed Limits

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snailracer

Über Member
^^^
Speed limits were introduced because of motor vehicles (steam powered back then) - it is therefore ironic that some cyclists worry about annoying motorists by exceeding them.
 

lit

Well-Known Member
Location
Surrey
Are you sure? You may not be able to be trapped by a speed camera but that isn't the same as it being legal.

What would happen if you passed a camera equipped police car that can validate its speed?

If it is legal for a bike to ignore the speed limit, then I think drivers would have a good reason to be p'd off

100% positive. Coming back down a slight hill from Surrey once, there were police doing speed checks on cars (the old A3 Portsmouth Road between Hampton Court Bridge and Esher) and I was doing 30mph and the policeman and woman just gave me a smile as i went past - the road is 50mph for cars anyhow, should be 40 though.

I've never read of a cyclist done for speeding on public roads, richmond park is the only place you can be (if they catch you of course).
 

GFamily

Über Member
Location
North Cheshire
Speed limits on the roads do not apply to cycles.

Except on roads in Royal Parks, where speed limits are applied by a different Act of Parliament.

Cyclists in Richmond Park have been issued with FPNs for exceeding the 20mph limit, and the Metropolitan Police have confirmed that (as far as they are concerned) the limits do apply.

I am not a lawyer, but I have tried to read the act, and it is not entirely clear that the law relating to speed limits was intended to apply to cyclists*, but it has been applied, and you would probably have to go to court with a good barrister to win your case against a FPN.



* As I recall (it was several years back that I looked at it), there are other place in the Act that specify what is, and what is not allowed - in those places the wording used is something like 'motor vehicles and pedal cycles'; however, the section that applies speed limits to the park roads, only mentions vehicles.
 

Parrot of Doom

New Member
I'd rather motorists paid attention to their surroundings and relevant hazards, than look at their speedometer every 5 seconds to ensure they're not exceeding an arbitrary limit.
 

jds_1981

Active Member
Typically within Hull, 20 mph zones have achieved reductions[<a href="http://www.publications.parliament.uk/pa/cm200102/cmselect/cmtlgr/557/557ap80.htm#note106" >106] in injury accidents of:
— Total accidents -56 per cent
— Killed & seriously injured accidents -90 per cent
— Accidents involving child casualties -64 per cent
— All pedestrian accidents -54 per cent
— Child pedestrian accidents -74 per cent. It is estimated that at the end of 1999, 390 injury accidents had been prevented within the 20 mph zones which had been previously installed. 122 of these would have involved injuries to children.


The reason for these reductions is simply because of the reductions in average vehicle speeds which 20 mph zones enforce through their engineering measures. For example, road hump schemes typically see reductions in speed from the high 20's to around 17 mph.

http://www.publicati...557/557ap80.htm

While that points strongly towards correlation, the data is still pretty crap, or at least used in an odd way, which I'm going to go out on a limb for and claim is being used to bias an argument.

Firstly there is a table with values in, then immediately below your quotes which show different values..
Child casualties292 218-25 per centThen
— Accidents involving child casualties -64 per cent
WTF? Oh, it's using different years...

Also the table compares Hull against Great Britain, which really isn't a like for like comparison.
Also the table shows that the introduction of speed bumps and limits increased (relatively) child cyclist casualties compares to 'Great Britain' by 7%.

Moving onto their survey of opinions (Which are often a very unreliable source to get 'facts' from)
— 25 per cent of respondents felt that there was less traffic since the 20 mph zone had been installed.
So what did the other 75% think? I'm going to guess some split between 'no difference' & 'more', so their selectiveness is quite a weasel figure.
Similar for the walking
— Over 25 per cent of respondents said that they walked or cycled more since the scheme was introduced.

It'd be nice for once if these reports compared like-for-like data in a fairly raw format.
 

pshore

Well-Known Member
The speed limit's will be for cars, buses, motorbikes etc. You can't limit the speed of a bicycle on the public highway, it's like telling pedestrians to walk slowly.

Aye. Until cycles are legislated to have speedos fitted, you can't expect riders to know what their speed is.

However, there are still laws to catch idiots who are endangering others such as careless cycling.
 

dawesome

Senior Member
While that points strongly towards correlation, the data is still pretty crap, or at least used in an odd way, which I'm going to go out on a limb for and claim is being used to bias an argument.

Firstly there is a table with values in, then immediately below your quotes which show different values..
Child casualties292 218-25 per centThen

WTF? Oh, it's using different years...

Also the table compares Hull against Great Britain, which really isn't a like for like comparison.
Also the table shows that the introduction of speed bumps and limits increased (relatively) child cyclist casualties compares to 'Great Britain' by 7%.

Moving onto their survey of opinions (Which are often a very unreliable source to get 'facts' from)

So what did the other 75% think? I'm going to guess some split between 'no difference' & 'more', so their selectiveness is quite a weasel figure.
Similar for the walking


It'd be nice for once if these reports compared like-for-like data in a fairly raw format.


It's pretty straightforward. Higher speeds increase the likelihood of collisions and increase the severity of these injuries. The only reason they're using different years is because the 20mph zones didn't exist in different years, obviously. Speeding is reported as the number one anti-social behaviour in the British Crime Survey, unless you are arguing that drivers should drive at any speed they like and use public roads as their own personal racetrack I'm not sure what your point is. Do you know the difference in the likelihood of death at 20 mph collisions versus speeds above 30?
 

Norm

Guest
Do you know the difference in the likelihood of death at 20 mph collisions versus speeds above 30?
Yes, but do you know the difference in the likelihood of collisions at 20 mph versus those at speeds above 30mph?
 

dawesome

Senior Member
I'd rather motorists paid attention to their surroundings and relevant hazards, than look at their speedometer every 5 seconds to ensure they're not exceeding an arbitrary limit.

Do yu find yourself unable to drive safely without checking your speedo every FIVE SECONDS? You don't think, maybe, there are other things you should be concentrating on? It's not hard for a competent driver to know pretty accurately whether their speed is above or below the posted limit, if you are unable to drive on public roads without gazing at your speedo have you considered extra tuition? It's a rudimentary part of safe driving that most drivers manage with no problem. If you collided with a vulnerable road user and offered as a defence, "I was staring at my speedometer" do you reckon you'd get off?
 

dawesome

Senior Member
Yes, but do you know the difference in the likelihood of collisions at 20 mph versus those at speeds above 30mph?

Yep.

TRL 421,

‘The effects of drivers’ speed on the frequency of road accidents’ published in March 2000.

This study was designed to discover the speed-crash relationship. The authors looked at 300 sections of road, made 2 million observations of speed and got 10,000 drivers to complete questionnaires. They found that
  • the faster the traffic moves on average, the more crashes there are (and crash frequency increases approximately with the square of average traffic speed)
  • the larger the spread of speeds around the average, the more crashes there are
They also found that:

  • drivers who choose speeds above the average on some roads tend also to do so on all roads
  • higher speed drivers are associated with a significantly greater crash involvement than are slower drivers
For these reasons they conclude that the speed of the fastest drivers (those travelling faster than the average for the road) should be reduced. The study confirmed what is described as a ‘robust general rule’ relating crash reductions to speed reductions: for every 1 mph reduction average speed, crashes are reduced by between 2-7%. More specifically, the crash reduction figure is around

  • 6% for urban roads with low average speeds
  • 4% for medium speed urban roads and lower speed rural main roads
  • 3% for higher speed urban roads and rural main roads
http://www.chapmancentral.co.uk/wiki/ABD's_Lonely_Factoid
 

dawesome

Senior Member
Come on, this is basic biology. A human can run at 20 mph. That's what the body, our bodies, are designed for. Impact collisions above this speed are lethal, your internal organs become detached and you bleed to death, if the trauma of the impact itself doesn't kill you. Our bodies are designed to withstand running into a tree at 20mph tops. Above 20mph you are much more likely to die. 20mph zones save lives because impact speeds are at a safer level.
 
OP
OP
martint235

martint235

Dog on a bike
Location
Welling
It would be a pity if you were to be opposd to 20mph limits nationally on the basis that some drivers in London might be upset at being overtaken by cyclists on a bridge which few of us have ever heard of.:sad:

I'm not opposed to them. I'm just not keen on bringing in a law that gives a guy in 2 tons of steel next to me, more reason to dislike me. My point is that if cyclists want them, they should at least abide by them.
 

BentMikey

Rider of Seolferwulf
Location
South London
Greenwich I think is a Royal Park. Chances are that in this park the 20mph limit is enacted by a bye-law that makes it also applicable to bicycles. That means us cyclists can also be done for speeding here, as regularly happens in Richmond Park. The rest of the public highway, however, you can't.

Like most I accept that despite it being totally legal, there's some sort of moral aspect which means when I go above the speed limit for motor vehicles, I do it rarely, and not by much.
 

Parrot of Doom

New Member
Do yu find yourself unable to drive safely without checking your speedo every FIVE SECONDS? You don't think, maybe, there are other things you should be concentrating on? It's not hard for a competent driver to know pretty accurately whether their speed is above or below the posted limit, if you are unable to drive on public roads without gazing at your speedo have you considered extra tuition? It's a rudimentary part of safe driving that most drivers manage with no problem. If you collided with a vulnerable road user and offered as a defence, "I was staring at my speedometer" do you reckon you'd get off?

As a driver of 20-odd years and someone who took and passed the IAM course, I think my driving isn't too bad. Five seconds was, of course, an exaggeration, but I do not believe that rigid enforcement of speed limits is beneficial to road safety.

BTW, I break the speed limit all the time - pretty much every day. Sometimes I drive massively under the speed limit. I use my observation to judge what is a safe speed, not a number on a stick. Clean licence too, and always has been.
 
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