Indicated speed vs GPS speed

[samanjo]

I rode with my GPS for the first time yesterday and noticed that the indicated speed is a lot slower than the true speed eg.

Bike speedo at 85 km/h = 80 km/h on GPS

Bike speedo at 106 km/h = 100 km/h on GPS

Bike speedo at 128 km/h = 120 km/h on GPS

Has anybody else noticed this?

My bike is a 2015 NC750X

[Deleted]

And your GPS is probably only accurate to around 10m when stationary!

I wanted to check the top speed of my Fireblade. The digital clock went as high as 299km/h (max display on some digitals) and I was convinced that the bike couldn't do 299.

So I fired up a GPS unit, stashed it securely under the seat and headed out to an "undisclosed location".

After a few runs at 299, stopped and reviewed the GPS....max speed achieved = 288km/h which is about a 4% error. Your figures are around 6% so we are probably very close to the truth.

Haven't checked the NC yet, but I doubt it will hit 288!

[DaveH]

This is normal on any vehicle. And then there is the speed trap machines that the spied cops use. Which one tells the truth?