Speedometer Error with R1250RSs & TFT Screen

[Grumpy Goat]

The UK guys on the RS forum argue it's that way by law over there.
I think it's a dumb law.

I have heard the same thing and personally I think it is anecdotal "inaccuracy", to put it in PC terms.

I seem to recall seeing a UK (?) statute that limits the error which is a far cry from setting forth some margin that speedos must be over by. I think I saw that the tolerance was biased towards overstating the speed and not understating it, which makes absolute sense. BUT there was nothing to say that it shall not be zero.

UPDATE - After typing the above I Googled "UK law regarding speedometer accuracy" and found the top hit being:

The law for car speedometers in the UK
A speedo must never show less than the actual speed, and must never show more than 110% of actual speed + 6.25mph. So if your true speed is 40mph, your speedo could legally be reading up to 50.25mph but never less than 40mph.Feb 11, 2022

I will go on record here - If any vehicle of mine, including my beloved RS, were to, by design (i.e. not be fixable) show me 50 mph when I am doing 40 mph I will fire it on the spot - no questions asked, no ifs and buts.