12OClock Labs speedo correction

My concern is with an accurate speedometer not the odometer. My ECU correction makes mine spot on. As for travel and fuel stops, once you correct the speedo you learn how many miles you can run on the odometer before a fuel stop. It is pretty consistent. With all that said, it is a moot point because I setup a phone mount and the GPS from my phone gives me my speed. I installed a USB jack on my handlebar with a voltage display for easy hookup. I do question the accuracy of the voltage indication and have yet to check it against one of my good digital multimeters. My camera won't capture the numbers on the display very well. The voltage readings appear rather high at highway speed showing 14.8 to 15 volts. This seems rather high considering the series regulator I have installed.