Yes, I am struggling with the same issue. I called Lectric and said it was working and wanted a replacement on the monitor. They said it was in the motor. No one will work on the motor. So my choices were to ignore the fact that I went 20 miles and it registered 10.8 and only went 5-8 mph, or put a bike computer on the bike, or adjust the P06 rating and see if that works. Lectric said that may or may not work. My ? is why doesn't Lectric set that before they ship it out. Here I was thinking They sold a defective product, and much worse, I bought off on it. So nice of them to acknowledge that. Ok, I'll be nice. So off to the grade school track I went. I Hit the + and - button for a few seconds and up popped Setting P01. but I want P06 for tire size. So I hit the on off switch to scroll thru the P setting until I got to P06. I set it at 40 even though the default was at 22 per the manual. Around and around the track I went 4 times. (a mile). Too much, I went 1.5 miles. I eventually narrowed it down to 25.0 before I hit 1 mile on the nose.
So yes, I believe it is 25 point something. It might depend on how inflated you have the rear tire. I believe mine was close to 30psi, recommended for the 2.0 tire.
All of a sudden I was going 10-13 mph instead of 5-8, too. But I can't check that out till I ride with my buddy and we match mph.
All in all, I thought I was doing pretty good for a guy turning 73 to keep up at 5-8 mph with my buddy who was doing 10-13.
Just my thoughts.