Last week I purchased a new wireless Cat Eye Cyclometer, model MC100W.

A tech at the bike shop calibrated it for me based on my bicycle wheel size. He had a tricky time with it, and complained that Cat Eye had changed their process for programming their cyclometers after YEARS of doing it ONE WAY for most models. I said "better you than me; I'm not too swift programming computers."

Well, having just started commuting with it, I noticed on the commute today that the total miles once I reached work was about 1 mile LESS than what my previous Cat Eye used to read on a different bike (calibrated by a different tech.)

So either the new Cat Eye is wrong, or the old Cat Eye was wrong. If the new Cat Eye is wrong, and as a result it's giving me total mileage that is LESS than what it should be, that would also mean that during my ride the speedometer is giving me a lower number than what I'm actually doing, correct? So if it says I'm doing 15mph, I might be really doing 17mph.

Do I have that right?