Here in my little town they love to put the unattended radar units out that tell you how fast you're going. Usually they put them in 25 MPH zones and they flash whenever you go more than 30. I asked the police chief to put it out on the four lane so I could calibrate my speedo without exceeding the speed limit so much next time

The look he gave me was NOT pretty

My speedo is about on below 45 but 5 mph high at 60 and above.