I recently installed a new Trek Incite 9i bicycle computer on my road bike. I already have one of these devices installed on another bike and it works fine on my other machine. However, my newly installed computer is giving me incorrect readings. For example, I did a short ride this morning and it said that my max speed was something like 55 MPH and I'm pretty sure I was not going that fast! I don't know how fast I went but, it was probably between 30 and 40MPH. It also said that I road something like 17 miles when I probably road about 11 miles. I noticed that the instaneous speed seemed higher than what I was really going.
When I entered in the wheel size into the computer, I couldn't find my tire size (700x26c) so I selected 700x25 instead. Would this slight difference in tire dimension be responsible for such wildly inaccurate readings? Since I'm getting faster measured values, I'm assuming that the computer thinks that my wheels are much larger than they really are. Or could it be that the sensor is somehow incorrectly measuring the wheel revolutions?
Thanks in advance.