GPS speed and TFT display - the same ?

[Pepsie]

I thought the speedo on the bike was supposed to run a little high.

Now I've got my nav 6 on my S1000XR Gen 2, the TFT and GPS speed show the exact same, sometimes the GPS shows I'm faster than what my speedo is saying.
On my S1000XR Gen 1, when I was going 70 mph, I would be going about 67 mph on the GPS.

On the Gen 2, 70 mph on display = 70 / 71 mph on GPS.


Does the NAV sync with the TFT and make it so that it's GPS accurate? or is my speedo running high?

 

[jetjock]

You can alter the accuracy of the Speedo using a computer or a GS911 . Looks like yours has been changed .

I believe the TFT gets its info from rotation of the transmission

 

[Pepsie]

You can alter the accuracy of the Speedo using a computer or a GS911 . Looks like yours has been changed .

I believe the TFT gets its info from rotation of the transmission

Damn I didn't know you could do that, I guess the previous owner has done this..

 

[jetjock]

Damn I didn't know you could do that, I guess the previous owner has done this..

Yeap. I’ve done the same . My speedo reads around 1 mph less than my GPS . Before it was about 8% more

 

[Neil W]

When in the job we tested a few types of sat navs against calibrated speedos, pro laser and muniquip and as long as the satellite signal was strong and not blocked by tall buildings they were always spot on regarding ground speed.
In comparison with vehicles standard manufacturers speedos which were all over the place , often well over 10% out.

 

[Mr Bean]

I understood that the GPS figure was only accurate on level ground. Could this provide an answer?