Ask an expert

With the coming "no tolerance" to speed limit, where can we get the accuracy of our speedos checked. And what is the expected tolerance figures of the calibration?

I think the "no tolerance" issue may have been a little misunderstood in the media late last week, however the rules are the rules, so while police may exercise a tolerance if they choose (and which they usually do), we should all understand that the speed limit is the speed limit, so we can still be ticketed for exceeding it.
Regarding speedo accuracy, there is a global standard for speedo accuracy and no speedo shall under-read. However, the standard allows for over-reading by (believe it or not) up to 14% at some speeds.
So while I don't think you have anything to worry about, instrument specialists such as Robinson Instruments can check speedo calibration.

If you take your car into (some) Testing stations that do COFs on Taxis, some will have rollers for testing taxi meters and can/may do a speedo test for you. This will test your vehicle at benchmark speeds (50, 70,100 kmh) and will take into account wheel/tyre changes that differ from original equipment. Of course, there will be a charge for this but will give you a good indication of how much over (normally) your speedo is reading.

I strongly believe that even if you have your vehicle's speedo calibrated by experts the Police will point blank totally refuse to believe anything that you say. They will only believe their own equipment and you will be unable to prove it to be incorrect.

Yes, of course you will be breaking the law if you're speeding whether your speedo is correct of not.
However, as we said before, the standard requires for speedos to read either correctly or to over-read. No cars will under-read from the factory, so unless something has been modified (ie; bigger rolling circumference wheels etc), you should not have anything to worry about.