On the road testing of the Speedometer...

I have been driving and I can't seem to get the right reading from my speedometer. While everyone should be doing 55 mph my bike says 45 mph.

Is there a way to check it?

 

I can think of four different ways you could do this: 1. A GPS would give you real time readout of your speed. 2. Find some measured miles on the highway. Some times you can find small signs, like 6" by 18" next to the road with just a number on them, each sign one number higher than the previous sign. But this would require using a stop watch while riding. 3. Getting someone in a vehicle with a speedo you believe is acurate to pace you. 4. Or the easiest is just ride like hell past the next cop you see. They'll be more than happy to tell you how fast you were going.

 

The last part sound like the easiest. I guess I can use the mile marker method. Who says that algebra would never get used.