The wear in your tyres will give you a speed inaccuracy on your speedo alone, hence the leeway.
It's not a myth.
The percentage is law but many constabularies allow 2 or 3 mph above this percentage before taking action.
 
The wear in your tyres will give you a speed inaccuracy on your speedo alone, hence the leeway.
It's not a myth.
The percentage is law but many constabularies allow 2 or 3 mph above this percentage before taking action.

Nothing to do with the Law. 10% +1 was a figure agreed many years ago at the then Association of Chief Police Officers (ACPO), now the National Police Chief's Council. It was never Law and local Police Forces were never actually required to follow it, though most did. Famously Richard Brunstrom, Chief Constable of North Wales until 2009 and ACPO's Head of Policing Policy, tried to push a zero tolerance policy in North Wales, crushing two cars and using footage of a decapitated biker to advertise the dangers of speeding (Probably should have spoken to the family first Richard).

As said, it is now down to the local Safety Partnership who are absolutely driven by safety and not profit........
 
Sigh........drives me mad when people speculate and believe the utter rubbish others say based on nothing more than their own or others obtuse opinion.

If you want to know the definitive position......

Look up the Sentencing Guidelines for summery only offences.

https://www.sentencingcouncil.org.uk/offences/magistrates-court/item/speeding-revised-2017/

A fixed penalty notice is a NOT a conviction, it is an offer to discharge your liability from prosecution by paying a fixed penalty. You have the choice to go to court and be prosecuted OR pay the fixed penalty.

On a UK motor way the limit is 70 (for car PLG) if your recorded speed is under 90 you will not be disqualified.
If your defender is classed as an LGV this would be an aggravating factor, although in itself not enough to elevate the starting point to the next band.

View attachment 166940

PS the Police have nothing whatsoever to do with setting the camera trigger limits, this is done by the local Safer Camera Partnership, it is 2MPH above the limit as a minimum.
Calibration arguments will not work as each camera self calibrates and provides secondary report for each offence, this calibration is then verified by a site visit at set frequencies, whereupon a sec 9 standard statement to that effect is provided.

I got my figures from a North Yorkshire police officer when I worked at Ripon. You can believe what you want though.
 
Met Police biker on another forum I frequent is saying that this is a social media myth and there is no truth whatsoever.
 
I think the 10% gets dragged in from vehicle construction regs, which allow speedos to over-read by up to 10%. Never allowed to under read. So, if your speedo shows 70, in fact you might be doing 63..... So some feel that means you could have speedo showing 77 and in fact only doing 70.....follow?

Trouble is you might have a completely accurate speedo and actually be doing 77....

Of course manufacturers wouldn’t play the 10% to make you think your vehicle is faster would they...? ;-)

I’ve ridden my bike alongside a calibrated police bike, and the speedo shows 77 when actually doing 70. Who’d have thought.... ;-). Cheers A
 
Of course manufacturers wouldn’t play the 10% to make you think your vehicle is faster would they...? ;-)

So if the odometer is driven from the same data that feeds the speedo, a car with an inbuilt 10% over-read would get to the warranty mileage 10% quicker....no I'm sure they wouldn't do that......
 
Shockingly my speedo reads bang on according to both phone GPS & TomTom within 1mph or so. Which I like.

Either way just look at the gantrys big yellow box on the left do below 70.
 
Shockingly my speedo reads bang on according to both phone GPS & TomTom within 1mph or so. Which I like.

Either way just look at the gantrys big yellow box on the left do below 70.

New cameras on smart motorways have small, difficult to spot grey cameras that don't need tell tale white lines on the tarmac.
 
I got my figures from a North Yorkshire police officer when I worked at Ripon. You can believe what you want though.
Well we have started to see laser vans on our roads (North Yorkshire ) recently and my mates wife was issued a notice at 32mph in a 30 zone, attended a speed awareness course first time then went and did it again.
They seem to favour spots where you just pass a 30 sign and may not have brought your speed down quickly enough.
Always wondered how they would react if you turned up for the speed awareness dressed as the stig.
 
Well we have started to see laser vans on our roads (North Yorkshire ) recently and my mates wife was issued a notice at 32mph in a 30 zone, attended a speed awareness course first time then went and did it again.
They seem to favour spots where you just pass a 30 sign and may not have brought your speed down quickly enough.
Always wondered how they would react if you turned up for the speed awareness dressed as the stig.

To be fair, I worked at Ripon back in 2008-2010, so things have probably changed a little. He was an armed response officer, so may not be up to speed on things!
 
The wear in your tyres will give you a speed inaccuracy on your speedo alone, hence the leeway.
It's not a myth.
The percentage is law but many constabularies allow 2 or 3 mph above this percentage before taking action.
Tis a myth. The apco guidelines were just that, guidelines. The speed limit is finite. Ratty got done for being 1mph over.
New cameras on smart motorways have small, difficult to spot grey cameras that don't need tell tale white lines on the tarmac.
none of the cameras need the white lines. Smart motorways have the yellow cameras on the left hand of gantrys, the grey boxes on over head gantrys and the infra red on top of cantilever matrix boards. The fella from CP told me the boxes only cover the outside lane and aren't always on, the matrix signs cameras cover all lanes and are always on. Not sure how trust worthy that was, and probably out of date even of it was correct.
 
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Not law, the old 10% +2 is a guideline and discretionary only

Plus or minus 10% at indicated speed is the old speedo calibration allowance up to 2001, it has to be applied to vehicles made before that date. That is why speed cameras are set that way. After that, actual speed can be under indicated but not over. EU ruling 1999. Enforced in UK from 2001. So any vehicle made before that can legally be doing up to 77 mph at an indicated 70.
 
Plus or minus 10% at indicated speed is the old speedo calibration allowance up to 2001, it has to be applied to vehicles made before that date. That is why speed cameras are set that way. After that, actual speed can be under indicated but not over. EU ruling 1999. Enforced in UK from 2001. So any vehicle made before that can legally be doing up to 77 mph at an indicated 70.

If I'm doing 77 mph in me Series a ticket is the last of me worries :eek::D
 
The wear in your tyres will give you a speed inaccuracy on your speedo alone, hence the leeway.
It's not a myth.
The percentage is law but many constabularies allow 2 or 3 mph above this percentage before taking action.

Wear in your tyres will show a higher speed on the speedo than you are actually doing. If you fit larger rolling radius tyres on than standard, you will be going faster than the speedo indicates. Old rules updated in 2001 were that the speedo can have a actual speed 10% error up or down when 30 mph is indicated. Goes back to the time when there was no speed limit anywhere other than 30 mph max in built up areas.
 
I think the 10% gets dragged in from vehicle construction regs, which allow speedos to over-read by up to 10%. Never allowed to under read. So, if your speedo shows 70, in fact you might be doing 63..... So some feel that means you could have speedo showing 77 and in fact only doing 70.....follow?

Trouble is you might have a completely accurate speedo and actually be doing 77....

Of course manufacturers wouldn’t play the 10% to make you think your vehicle is faster would they...? ;-)

I’ve ridden my bike alongside a calibrated police bike, and the speedo shows 77 when actually doing 70. Who’d have thought.... ;-). Cheers A
God you must have been peddling bloody quick
 
I think the 10% gets dragged in from vehicle construction regs, which allow speedos to over-read by up to 10%. Never allowed to under read. So, if your speedo shows 70, in fact you might be doing 63..... So some feel that means you could have speedo showing 77 and in fact only doing 70.....
You’re not wrong with “vehicle construction regs” bit, my disco speeds reads 70 while the windscreen mounted sat-nav reads 65, my normal car the dash sat-nav reads 70 and so does the digital speedo and both match whatever speed I’m doing + - 3mph
 
I got my figures from a North Yorkshire police officer when I worked at Ripon. You can believe what you want though.

I tend to believe the law, and not the police, mainly because I train them for a living, admittedly i don't work in North Yorks though .... ;)
 
Nothing to do with the Law. 10% +1 was a figure agreed many years ago at the then Association of Chief Police Officers (ACPO), now the National Police Chief's Council. It was never Law and local Police Forces were never actually required to follow it, though most did. Famously Richard Brunstrom, Chief Constable of North Wales until 2009 and ACPO's Head of Policing Policy, tried to push a zero tolerance policy in North Wales, crushing two cars and using footage of a decapitated biker to advertise the dangers of speeding (Probably should have spoken to the family first Richard).

As said, it is now down to the local Safety Partnership who are absolutely driven by safety and not profit........

Correct, remember not to confuse a prosecuting agencies decision to prosecute with the material fact of weather or not a law has been broken, the law is 1 mph over = offence committed.

Police prepare evidence and then decide to either:
a) offer a FPN
b) report by way of summons for prosecution by CPS who actually decide to prosecute, (in practice excessive speed evidence is a standard format so will always result in a prosecution unless CPS process spots errors in the evidence.

The offence relates to the actual speed of the vehicle and not what the driver believes the speed to be for whatever reason, whilst your speedo's inaccuracy may be a factor, a driver referencing this does two things ;

a) admits the vehicle they were driving was in an unroadworthy condition if its underreporting the speed,
b) QED admits they have no idea what speed they were actually doing
Faulty speedo fine = £2,500 for goods vehicles ( so thats most of us defender owners) and £1,000 for other vehicles.

Ironic really that this amount of money goes onto securing (in the main) the collection of fines, bit of a contrast when you look at other offences such as burglary. Try looking at the penalties for tax evasion balanced against sexual offences for example.....

;)
 

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