Used my non OEM Sat Nav for the first time in the FL2 yesterday and was a bit surprised (and worried) about how accurate the speedo is. Having previously worked to a 8-10% discrepancy on the Audi, I found it matched the sat nav exactly to 70mph and at 80mph the speedo read about 82 and at 90 it read 92-94. Decided to stop there!

At least I know why nothing ever seems to overtake me and I'll go and sit by the letterbox and wait!

I have always found on my Tom Tom with various cars the Tom Tom reading was 2-3MPH slower than the actual car speedo.

I've made a similar comparison with both Garmin and TomTom satnavs, I agree the FL2's speedo is consistently quite accurate, it does over read, but only just. So 'you get what it says on the tin'.

With other cars I've always thought I'm OK if the needle creep a little over the target speed, not something I do in the FL2

It is a mandatory requirement on car manufacturers that the speedo cannot read slow, i.e. the tolerance is one way and the reading can only be higher than real road speed. It can never be the case that you were doing an indicated (e.g.) 30 and be actually travelling over the speed limit.

Car speedometer will therefore always read the same or higher speed than GPS but technology has improved now that speedo senders are electronic rather than mechanical so things are much more accurate. The limit is up to 10%+10 km/h above actual speed but don't ever rely on it being so wrong!

Remember that the tyres wear and become smaller so for each revolution, the car is going a shorter distance for each rotation of the driveshaft. Speedo readings will increasingly over-read the real speed with time and wear.

Chris Gone... 2013 XS TD4 Manual Firenze Red
Gone... 2008 (09MY) XS Td4 Manual Stornaway Grey
Prior... 2003 G4 Discovery 2, 1998 Disco 1 and 1997 Disco 1 Company car before that
Also gone in Nov'13, after 7.5 yrs, to new owners with time for more TLC - 1980 Series III 88
Current 2015 Discovery Sport HSE 2.0

Speedo's are very accurate these days and have been for the last 10+ years.

My '98 Audi A3 remains only a few km/h off of the GPS true speed all the way up to 250 km/h (155 mph), so the 10% rule that people previously used is well out of the window now. Once you've tasted GREY you'll never go back!

Here in the UK if you get a speeding ticket it will clearly show the speed limit where the offence took place but will also show that how it is calculated as follows:-

SPEED LIMIT + 10% + 2MPH

So you can drive at 79mph in a 70 limit before you will get done for speeding.

I know this as my farther was recently done for speeding travelling south on the M74. ______________________
2011 Full Fat RR 4.4 TDV8
2012 FL2 SD4 Auto HSE
2013 Kawasaki Versys 650

Based on Dave's info above, has anyone actually been caught whilst doing less than:-
36 in a 30 zone,
47 in a 40 zone,
58 in a 50 zone,
69 in a 60 zone, or
80 in a 70 zone?

Whether it has happened to anyone here I don't know but I think you'll find the answer is yes.

To be 'done' then there has to be an excess over the applicable limit. In order to secure a conviction the action speed is set at something which is beyond the tolerances, I understand there are different criteria that determine the 'action' speed. i.e there's an allowance for the known allowable variance in speedos, plus there are sometimes other factors if you read the safety camera forums then there is talk of another 2 - 4 % which may be factored in.

Again reading these forums you get the impression that its camera where the tolerance is set the tightest. Tolerances are can be helpful if you have a momentary lapse but I wouldn't rely on them all the time.

However if you're driving on the motorway and its face to face by a enforcement by a 'real' policeman then the chances are these allowance will be more generously applied This of course is why we all hate the cameras

lem_jpm wrote:

Based on Dave's info above, has anyone actually been caught whilst doing less than:-
36 in a 30 zone,
47 in a 40 zone,
58 in a 50 zone,
69 in a 60 zone, or
80 in a 70 zone?

Yes 46 in a 40. I went past the camera at what I thought was about 43 mph. Either I was wrong or the speedo was wrong or the camera is calibrated incorrectly. Either way I was doing over 40 so I had to attend a Speed Awarness workshop to avoid receiving 3 points on my licence.

To clarify. The 10% + 2 mph is not the maximum speed at which you can drive at but the level at which you can legally be prosecuted. ie, drive at 35 in a 30, 46 in 40, 57 in a 50, etc and expect a nice letter from you local constabulary on your door mat. You are allowed up to 10% + 2, not including.

Steve

Edit: This is my first ever motoring infraction and I was driving my old Peugeout 307 CC on the way to Statford to collect my new Freelander 2

Scottish speed cameras must be calibrated differently then, can quite happily pass them at 78 - 80mph without triggering them. ______________________
2011 Full Fat RR 4.4 TDV8
2012 FL2 SD4 Auto HSE
2013 Kawasaki Versys 650

24772433 wrote:

This is my first ever motoring infraction and I was driving my old Peugeout 307 CC on the way to Statford to collect my new Freelander 2

I can understand why you had a lapse in concentration.....a new fl2 will do that to a person  Once you've tasted GREY you'll never go back!

In speaking to a cop I know involved in that sort of thing he reckons they are set to 83mph

[quote="24772433"]

lem_jpm wrote:

You are allowed up to 10% + 2, not including.

Have tested my Freelander 2 today against my Garmin 276C GPS. All in KM/Hr.

GPS Speedo
60 61.5
80 82
100 102.5
120 123
130 134

Speedo is very accurate and it's good to know what your actual driving speed is.