Satnav Speed

[handyjack]

How accurate is he speed indicated on a satnav?

 

[Burnerman]

I use a BMW Motorrad device which I think is a Garmin 5......it starts bonging at me if I'm 2 MPH over.
John

 

[DaveHerns]

Maybe he means is the speed shown on the sat nav accurate?

 

[Burnerman]

I compare the sat nav indicated speed with that on my digital speedo and it appears to be completely accurate, somewhat to my surprise.
The blessing is, if my sat nav is on my bike, I can't hear a thing
John

 

[alan333]

I reckon sat nav indicated speed is more accurate than a car speedo. There's a law preventing car speedos from under-reading, so generally they over-read.

 

[handyjack]

Have passed the same road side speed indicator three times showing my satnave and the indicator as he same. While my car speedo has shown me doing 2 mph faster.

 

[Spark123]

Do you have new tyres?

 

[foxhole]

Sat nav will me more accurate. Speedo on my old Cortina mk5 said I was doing 125mph.

 

[magicmushroom666]

Satnav will be quite accurate as long as your doing steady speed. It has to calculate an average value, so will be off while changing speed but very good when steady.

 

[Avocet]

Sat-nav will be very accurate. As has been said, bed at constant speed and ideally, in a straight line, but FAR better than the speedo. As has been said, it's illegal for the speedo to ever under-read, so all manufacturers give themselves a bit of a margin to allow for build tolerances and tyre circumference.