It's Official - inaccurate speedo
Discussion
I've always suspected my speedo read low - around 3,000rpm in top showing 70mph. Well not according to Mr. Plod's VASCAR! At that indication he clocked me at 91mph on the M11 this afternoon and has even promised to give me 3 points in exchange for £60 as well. Faulty/inaccurate speedo is no excuse so I have to roll over. They were in an unmarked old dark blue Modeo.
Stuart Martin of Cerberus Motorsport was supposed to re-adjust the transponder during a service last year but said the gap was OK and suspected the wiring. I'm still waiting for him to return (and will be deducting £60 from his bill).
Stuart Martin of Cerberus Motorsport was supposed to re-adjust the transponder during a service last year but said the gap was OK and suspected the wiring. I'm still waiting for him to return (and will be deducting £60 from his bill).
. They were in an unmarked old dark blue Modeo.
Stuart Martin of Cerberus Motorsport was supposed to re-adjust the transponder during a service last year but said the gap was OK and suspected the wiring. I'm still waiting for him to return (and will be deducting £60 from his bill).
A modeo ?
I think you should deduct the price increase in your insurance as well.
If a dud speedo isn't a good enough excuse, how else are you meant to tell how fast you're going FFS ?
Sorry to hear about the ticket. Could it be your tacho is out?.. 3000 rpm, that would give you a top speed over 180mph so unless your Chim is rocket propelled it must have been more than a tad over
I've always suspected my speedo read low - around 3,000rpm in top showing 70mph. Well not according to Mr. Plod's VASCAR! At that indication he clocked me at 91mph on the M11 this afternoon and has even promised to give me 3 points in exchange for £60 as well. Faulty/inaccurate speedo is no excuse so I have to roll over. They were in an unmarked old dark blue Modeo.
Now 3500 rpm would be more like 90 mph. Easy calc to do as a quick check, if top speed is around 160 mph at 6250 rpm you've got to be under 2800 rpm to keep under 70 mph... easily done though.
MC
I've always suspected my speedo read low - around 3,000rpm in top showing 70mph. Well not according to Mr. Plod's VASCAR! At that indication he clocked me at 91mph on the M11 this afternoon and has even promised to give me 3 points in exchange for £60 as well. Faulty/inaccurate speedo is no excuse so I have to roll over. They were in an unmarked old dark blue Modeo.
Stuart Martin of Cerberus Motorsport was supposed to re-adjust the transponder during a service last year but said the gap was OK and suspected the wiring. I'm still waiting for him to return (and will be deducting £60 from his bill).
Quite simply shity death! I would follow the £60 rebate on your bill with a swift kick to the cojones!
>> Edited by Big Chris on Friday 21st March 12:43
It gets worse. I changed my reg plate over Xmas and forgot to tell my insurance co. (Mannings). Phoned them first thing today and they are sending out a cover note - but commencing today. I may not even be insured at the time of the offence!
BTW - PC Plod (nice chap) said inaccurate speedo No Excuse. It's up to the driver to keep within the limit, and an inaccurate speedo could even be an aditional offence! Which arm do you want to begin with?
BTW - PC Plod (nice chap) said inaccurate speedo No Excuse. It's up to the driver to keep within the limit, and an inaccurate speedo could even be an aditional offence! Which arm do you want to begin with?
Could it be your tacho is out?.. 3000 rpm, that would give you a top speed over 180mph so unless your Chim is rocket propelled it must have been more than a tad over
Now 3500 rpm would be more like 90 mph. Easy calc to do as a quick check, if top speed is around 160 mph at 6250 rpm you've got to be under 2800 rpm to keep under 70 mph... easily done though.
MC
my speedo reads just under 90 at 3000 revs(griff 500 with t5 g/box),which would mean all is normal in that dept.dont forget 180mph isnt possible as the power/weight/aerodynamics wont allow it to rev that high in top gear.
>> Edited by mongoose on Friday 21st March 13:27
Now 3500 rpm would be more like 90 mph. Easy calc to do as a quick check, if top speed is around 160 mph at 6250 rpm you've got to be under 2800 rpm to keep under 70 mph... easily done though.
MC
my speedo reads just under 90 at 3000 revs(griff 500 with t5 g/box),which would mean all is normal in that dept.dont forget 180mph isnt possible as the power/weight/aerodynamics wont allow it to rev that high in top gear.
>> Edited by mongoose on Friday 21st March 13:27
the dodger said:
BTW - PC Plod (nice chap) said inaccurate speedo No Excuse. It's up to the driver to keep within the limit, and an inaccurate speedo could even be an aditional offence! Which arm do you want to begin with?
WTF is he on about, how on earth are you supposed to know if your speedo is inaccurate or not? How often does your speedo get tested?
Get the car on the rollers and get the operator to certify that it reads 70 when the car is doing 90. If the speedo says 70 then hoe can they do you for speeding?
Nik
I got shafted because of this as well.
I was driving out of Frankfurt one night and my speedo showed 70 kmph. I was unfamiliar with the area and I thought it was an 80 limit, it was actually a 50 which made things soooo much worse.
I got flashed by a revenue camera, my first reaction was to look at the speedo and it read dead on 70 kmph. So I thought, ok some points and a fine.
Got the NIP in 81 kmph on a 50 limit. Goodbye licence for 1 month.
Bunch of
I was driving out of Frankfurt one night and my speedo showed 70 kmph. I was unfamiliar with the area and I thought it was an 80 limit, it was actually a 50 which made things soooo much worse.
I got flashed by a revenue camera, my first reaction was to look at the speedo and it read dead on 70 kmph. So I thought, ok some points and a fine.
Got the NIP in 81 kmph on a 50 limit. Goodbye licence for 1 month.
Bunch of
I believe I'm right in saying the MoT states that Speedo accuracy must be within 10%. So maximum theoretical speed in the UK is 77mph. However, this goes totally against the whole zero tolerance thang. If you are within that ten percent zone, could you play one law off against the other? As I was stopped at 100plus (so ashamed) I couldn't field this prepared argument!
Speedos are allowed to OVER read by 10% PLUS 2.5mph. They must NOT under read AT ALL. This is the type approval requirement that all new mass-produced cars are built to. Most can manage to stay easily within this on the manufacturer's recommended rims and tyres (more like within 5% at most legal speeds). If it's a kit car or something that has been through the SVA test you get up to 10% plus 6.25mph (but still not allowed to over-read at all). Whichever way you look at it, it should be impossible to get in a car that has an under-reading speedo unless it has been modified or is poorly.
75 indicated, 69 true sounds quite fair... I use GPS to check my Speedo too, its about as good as you can get, really...
And IRC
I'm not sure when it changed but new cars used to be allowed +/- 10% because mechanical speedo's would usually overread at low speed (say 30mph), oversize wheels/tyres can soon lead to under-reading anyway. Now they can over-read only, and its not uncommon for the tacho to have a similar over-read, just so numbers add up, plug in engine diagnostic kit can give true rpm,
And IRC
I'm not sure when it changed but new cars used to be allowed +/- 10% because mechanical speedo's would usually overread at low speed (say 30mph), oversize wheels/tyres can soon lead to under-reading anyway. Now they can over-read only, and its not uncommon for the tacho to have a similar over-read, just so numbers add up, plug in engine diagnostic kit can give true rpm,
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