speed limit + 10% still legal?
Discussion
i seem to recall in the olden days that you were allowed to exceed the speed limit by up to 10% to allow for inaccuracies in the speedometer ie you would be allowed to travel at up to 77mph on the motorway before being liable to be stopped.
The general thought was that if you travelled at an indicated 80 or less on the motorway, where it was safe to do so, it was very unlikely that you would be stopped for speeding.
With the increased use of speed cameras, does anyone know if legally you cannot be booked for doing a true 77mph or less on the motorway? (obviously excluding areas where the speed limit is reduced) or is the 10% leeway an urban myth?!
The general thought was that if you travelled at an indicated 80 or less on the motorway, where it was safe to do so, it was very unlikely that you would be stopped for speeding.
With the increased use of speed cameras, does anyone know if legally you cannot be booked for doing a true 77mph or less on the motorway? (obviously excluding areas where the speed limit is reduced) or is the 10% leeway an urban myth?!
a) Speedos may overread by up to 10%, but may not underread by any margin.
b) If you exceed the speed limit by any amount, you are committing an offence, and your speedo will be showing a speed in excess of the limit because of a), so you know about it.
c) Police 'code of practice' *used* to allow for (limit+10%)+2. With all the targets these days, and camera tolerances, this may no longer be true.
(IIRC, IANAL, etc, etc)
b) If you exceed the speed limit by any amount, you are committing an offence, and your speedo will be showing a speed in excess of the limit because of a), so you know about it.
c) Police 'code of practice' *used* to allow for (limit+10%)+2. With all the targets these days, and camera tolerances, this may no longer be true.
(IIRC, IANAL, etc, etc)
I think the 'grace' afford to drivers depends on what force & conditions. I thought on a national wave it's 10% + 3 so a 70-MPH zone would be 80MPH, anything above you'd get fisted for.
This thread would be betting in the Speed plod & law as that where the BIB on here tend to hang out.
This thread would be betting in the Speed plod & law as that where the BIB on here tend to hang out.
that sounds logical...
i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod... i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod... i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
The 10% is simply a guide and should not be considered in any other way. It is not just the Police who use this guide but also local authorities. For instance some authorities will allow the 10% plus 1 mph so 30 becomes 30+3+1=34 other authorities however will have a tolerance of 2mph.
I believe and spoken with good friends that have served on traffic that as long as you are below the 10% fictation they would normally leave you alone
I believe and spoken with good friends that have served on traffic that as long as you are below the 10% fictation they would normally leave you alone
From what I've heard, some cameras are set for zero tolerance (allegedly) some are set with quite a healthy margin (allegedly the M25 variable speed limit cameras are triggered at 93mph when it's marked as 70....)
My experience of the mk1 human BiB is that many of them are actually pretty reasonable and will generally take atleast some account of how you're driving as well as absolute speed.
My experience of the mk1 human BiB is that many of them are actually pretty reasonable and will generally take atleast some account of how you're driving as well as absolute speed.
philcray said:
With the increased use of speed cameras, does anyone know if legally you cannot be booked for doing a true 77mph or less on the motorway? (obviously excluding areas where the speed limit is reduced) or is the 10% leeway an urban myth?!
The leeway comes from the ACPO *Guidelines* and are there (IMNHO) to allow for the inaccuracies in the process; your speedo and their camera, LIDAR, GATSO, WHY (and physics dictates there *are* inaccuracies in their equipment, no matter what the scamera "partnerships" say).But they are only guidelines, and if you're doing 70.00000000000000000000001 mph, you could theoretically be done for speeding. But can you imagine the fuss? Hence the leeway.
Chris71 said:
From what I've heard, some cameras are set for zero tolerance (allegedly) some are set with quite a healthy margin (allegedly the M25 variable speed limit cameras are triggered at 93mph when it's marked as 70....)
I have never heard of cameras being set for zero tolerance. And, aside from the fact that less than a handful of M25 variable cameras remain, I can't recall ever seeing them flash when those around me (
) have been making pretty good progress with no variable in operation. That said, I wouldn't fancy putting it to the test with a 3 figure fly-by though..Chris71 said:
My experience of the mk1 human BiB is that many of them are actually pretty reasonable and will generally take at least some account of how you're driving as well as absolute speed.
Seconded..
philcray said:
i seem to recall in the olden days that you were allowed to exceed the speed limit by up to 10% to allow for inaccuracies in the speedometer ie you would be allowed to travel at up to 77mph on the motorway before being liable to be stopped.
The general thought was that if you travelled at an indicated 80 or less on the motorway, where it was safe to do so, it was very unlikely that you would be stopped for speeding.
With the increased use of speed cameras, does anyone know if legally you cannot be booked for doing a true 77mph or less on the motorway? (obviously excluding areas where the speed limit is reduced) or is the 10% leeway an urban myth?!
1. If your speedo reads 77 mph and your vehicle is doing 70 mph you would be OKThe general thought was that if you travelled at an indicated 80 or less on the motorway, where it was safe to do so, it was very unlikely that you would be stopped for speeding.
With the increased use of speed cameras, does anyone know if legally you cannot be booked for doing a true 77mph or less on the motorway? (obviously excluding areas where the speed limit is reduced) or is the 10% leeway an urban myth?!
2. If your speedo is indicating 70 mph and you are doing 77 mph you are committing 2 offences, exceding the speed limit and driving with an illegal speedo as it is under-reading.
In 2 above you would be committing same 2 offences if you were travelling at 71, 72, 73, 74, 75, 76 or any speed above 70 mph.
philcray said:
that sounds logical...
i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod... i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
IMHO, nothing to worry about.i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod... i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
If they nabbed everyone doing less than 80 mph, then
they wouldn't have anytime for anything else.
I wouldn't condone breaking the law, and I certainly
don't go on the M6 very often, but when I do I see
a lot of traffic doing about 85-90 mph without problems.
IIRC the ACPO *guidelines* are three points up to 96 mph.
Quite how closely the guidelines are followed I
have no idea for the M6.
Some, not all, insurance companies ignore the
first three points anyway. Might be something
to look out for the next time you renew.
philcray said:
i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod... i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
Not speed cameras, but ANPR.
philcray said:
that sounds logical...
i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod...
LanCASH£££££££££re.i ask because i was driving northbound towards J31 of the M6 yesterday and i noticed that there was a police van parked under the bridge and what i assume was a speed camera on a tripod...
He often there. No worries. If you are at 10% +2 - then you might get a snotty letter telling you that you have been 
a naughty boy as "do you not realise that 1 mph above the lolly kills children all over the world in their millions. " (We know of folk who got such a letter. OK - it was not worded that way exactly but basically it could be interpreted as saying that ) At 10% + 5 across entire range of limits - LanCASH£££re will invite you to their Speed Awareness Course. Actually this ist a good course as all who give us info about it tell us that the ADIs are luke warm towards the scams - one of them was hit by one apparently in early scam years when course not offered.
. I should not laugh or gloat nor indulge in any "Schadenfreude", though as he does teach C O A S T. That why this course perhaps OK. All locals who tell us about it say no "digs at being done for speeding. They seem sympathetic that they were copped like that but those who do this course are all very much favourable about the refresher aspect und COAST learning curve. Despite these very safe blippers postive reactions und an FOI which indicate almost "zero re-offend" over one-three year period per existing records which they will hand over as this good PR
, I still think they invite the wrong people. The intrinsically safe ones who might just get a ticking off by police officer. But that professional officer would und should offer the course to those who in his truly trained professional opinion need it to make roads safer. The blippers do take heed of ticking off with COAST advice as normally decent in nature. These are people just like you Liebchen 
I think you probably OK given their cut off at 10% +2 for warning to 10%+5 for course und above this margin will earn you FPN to court summons if really silly or up to tot-up. (They used to be draconian. Locals rebelled
. ) philcray said:
i think my speedo was showing below 80 (and i drive a 15 year old Mercedes CE230 so probably not ultra accurate...) but feeling a touch paranoid!
Ach! I know one of relatives has a 17 year old Cavalier (in absolute mint condition und now starting to appreciate in value as a " pristine classic of its time". This old lady owner who related to Mad Doc (a maiden aunt) does not exactly speed but we thought it odd when she claim to drive past a scam at 40 mph in a 30 mph in LanCASH£££re with not one NIP. (She feel speed anyway. She felt car was at 30 mph. But she noted it read just under 40 mph as she pass, without noticing immediately, one hidden behind a bus shelter und spent 16 days allowing for post in shocked denial und disbelief as she was sure from experience it was about 30 mph, but could not recall a flash when quizzed by us. But she elderly lady now. In early 80s now. A bit frail but "on the button in the upper storey" (I had to laugh when she describe herself as a "Sunday driver" these days 
Not quite. I feel safe enough when she drive. I have to admire her. She fight breast cancer when aged 40. A fine lady. 
) But her old car? It under-read as normal at low speed by 3/4 mph. When her dash read 30 mph - our RA read 25 mph though. At her speedo dash reading of 70 mph - our RA told us 60 mph.
We took this car to track to really test. We found the faster we took her the wider the mis-read per the RA
We approach local dealer with view to correct the speedo. We told that the Chavalier batch of that year group of 1992/93 had a "problem" that way. The dealer could not be sure a new speedo would cure but the feisty old lady then bought an RA/Sat Nav. She happy enough with this old car which she only use to go to shopping mall in big burb at weekends. (When asked about week days - her reply was "I am not senile. They all idiots in the week. I go shopping when idiots are not on road with me."
)dcb said:
IMHO, nothing to worry about.
If they nabbed everyone doing less than 80 mph, then
they wouldn't have anytime for anything else.
I wouldn't condone breaking the law, and I certainly
don't go on the M6 very often, but when I do I see
a lot of traffic doing about 85-90 mph without problems.
IIRC the ACPO *guidelines* are three points up to 96 mph.
Quite how closely the guidelines are followed I
have no idea for the M6.
Some, not all, insurance companies ignore the
first three points anyway. Might be something
to look out for the next time you renew.
It depend where on M6. I do not recommend speeding around SHAP. Steve's vans are around there pretty often. He not like Lancs with a COAST course. As said - I think he OK. Like Mad Doc's aunty he feel a worry - but worst case scenario for phil would be Speed Course offer which I would take as that course which teach IAM driving from all reports - a decent enough deal to be very fair to the Lancs Prats. If they nabbed everyone doing less than 80 mph, then
they wouldn't have anytime for anything else.
I wouldn't condone breaking the law, and I certainly
don't go on the M6 very often, but when I do I see
a lot of traffic doing about 85-90 mph without problems.
IIRC the ACPO *guidelines* are three points up to 96 mph.
Quite how closely the guidelines are followed I
have no idea for the M6.
Some, not all, insurance companies ignore the
first three points anyway. Might be something
to look out for the next time you renew.
I do not condone "injustice/jobsworthy" but I will accept that this particular course has much merit all the same even if I worry over the invites being our safer drivers all the same.
But many insurers know that cop by scam? A bit meaningless these days as to "dodgy risk". The system then shoot itself in foot
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