Speedometer calibration

[blueq]

I just got my i3 2 days ago and I'm noticing that the speedometer is reading 2 mph higher than actual speed. Can that be calibrated or corrected by BMW easily?

I know this because Denver has a lot of radar speed limit signs to show your speed relative to the speed limit. My other 2 cars match what the signs say, but the i3 is reading 2 mph higher than the reading on the signs.

 

[Sparky]

All BMW's read 3mph high. I've had a ton them. Cannot calibrate.

 

[WoodlandHills]

All BMW's read 3mph high. I've had a ton them. Cannot calibrate.

Not all BMWs. The i3 is only 2 mph over actual as has been reported here previously....

 

[rtanov]

My impression is that this was a percentage up not a fixed mph value - both my e39's were showing about 5% above actual speed, have not measured the i3.

 

[WoodlandHills]

Several people have mentioned the 2mph error and I have it too. It seems to be a constant as its there at every speed I have checked it. I don't know the speed at which it kicks in though: is an indicated 4 actually 2? So far I know that 27 is actually 25, 37 is 35 and 42 is 40.

It makes it easy to set cruise control at the maximum legal speed with no guesswork. If there has to be an error for liability reasons, this is the best way to do it.

 

[elptex]

This has been discussed at length in this thread... http://mybmwi3.com/forum/viewtopic.php?f=10&t=1586

#search

 

[mindmachine]

Most car companies set the speedo to read fast by 1 to 3 mph for legal reasons.

 

[jadnashuanh]

Way back when, speedometers were often fairly accurate (at least the Germans). The EU regulations changed that...they still are, but with a known error mandated by regulations. Could they recalibrate it for the USA? Certainly, but it's not a big deal, at least to me. On most cars, you can get a 1-2% error from between when your tires are new verses when they are at the end of their tread depth service life. In theory, cars with built-in gps based navigations systems, could self-calibrate and be quite accurate. Don't know of any that actually do that, but we often don't get knowledge of the intimate details of this type of implementation.

 

[Boatguy]

Most car companies set the speedo to read fast by 1 to 3 mph for legal reasons.

My Mercedes is spot on, at least as calibrated by my friendly local sheriff's radar!