New cars and bikes are sold with speedos that read about 5-6% fast, as standard practice. It's mainly for legal reasons from what I understand. ie; if someone is in an accident and their speedo read slow they could blame the car.Local speed displays always show me going 3% to 6% slower than my speedometer because they are mounted at the side of the road and the angle creates an error.
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Selling the car with a speedo that reads a bit fast gives them legal protection
and a little safety buffer.
If you want your exact speed just put your GPS/phone on the dash and travel in a straight line for a minute or two, it will give a really accurate speed indication.