Thanks, Noracer. This is interesting information. It also makes sense. It looks to me like the only calibration on the bike PM is to dial the computer into the strain gage's tolerance variation using some kind of known reference. It still seems to me that the method used on the Kaiser, though perhaps not as accurate, would still be very close. Using more a mathematical approach to calculate the wattage, it still would be quite accurate since there are few unknowns in the calculation. Assuming that engineering and manufacturing were done correctly.