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Discussion Starter #1
While enroute to Newcastle and back at the weekend is was alerted by my Garmin to all the fixed and mobile speed traps.
Some are well out of date but some were accurate.

The problem was the indicated speed on the Sat Nav and the speedo varied according to the speed.

At 30 MPH not much in it

At 80MPH on speedo.....73 on sat nav.(If Sat Nav accurate I could have gone about 4 mph faster Ie 77 70 plus 10 percent.(Speedo would have shown about 85)

I reckon the Sat nav to be more accurate ...Don't know what a court would say though.

Anyone else noticed any variance.

Pomeo
 

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Pomeo,

Yes that sounds about right. Plod will normally allow 10% variance due to speedo and judging from your Speedo reading at 80, real speed will be 72/73 measured by Sat Nav.

I get same in the 166 and 156 using Road Angel (when it picks the satellite up!!)

166lover
 

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Yeah I noticed mine was a bit out too with my road pilot, was about 4 mph under at 80, so actual speed was 76, stay about the same all the way to 140 though! Ah the joys of the autobahn!
 

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I have always suspected my 166 was recording a faster speed but nothing to prove or disprove it. I have a Ducati ST3 which I think has the same problem, only even more pronounced (honestly officer...)
 

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Giulia Quad, Cayman GT4, Cayenne Turbo
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My speed says Im doing 100 when I'm doing 80 ????? \

HELP!
 

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Do they still have distance markers on the motorway - I haven't looked for ages? If they do, set your cruise control to whatever speed you want to check (say 60 mph) and time yourself between mileposts, you should be accurate to within second and that'll check you to within 1 mph. You can measure over a longer distance for more accuarcy.
Mike
 

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Discussion Starter #7
Do they still have distance markers on the motorway - I haven't looked for ages? If they do, set your cruise control to whatever speed you want to check (say 60 mph) and time yourself between mileposts, you should be accurate to within second and that'll check you to within 1 mph. You can measure over a longer distance for more accuarcy.
Mike
Good tip mike but they are probably well overgrown with grass so you cannot seen them.They will soon remove all the phones as nowadays almost everyone has mobiles and if you breakdown without a mobile it will be your fault.It will then be an offence to breakdown on the motorway not in possession of a mobile phone.

Pomeo
 
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