f_pp898624wrote a review of Pioneer Shimano Ultegra R8000 Single Leg Power Meter Crank Arm on November 14, 2019
Familiarity: I've put it through the wringer
I bought this because it was inexpensive, and I wanted a power meter on my rain bike. It was easy to set up, and as long as you don't mind the limitations of ANT+ (communication with phones), the whole thing is fine. The trouble is with its data. I have four other power meters, two Quarks, and two Power2Max NG (all spider-based, two sided). I have an Elite Suito trainer as well. Each device claims to be accurate within 1.5 to 2.5%. Each of these devices measures my power output to within 3-4 % of one another, generally. The Pioneer measures 10-15% lower in overall output, which isn't helpful for a number of reasons. I researched the matter and found that others, including professional reviewers, had experienced the same thing. Given that it's a strain gauge, and stress on the material in other places has the potential to alter data, I've made certain to torque everything on the crank to specs. I bought the Pioneer SGX-CA500 computer (which is an odd little duck) for 75$ on Steep & Cheap simply to update firmware, make sure calibration was correct...and to have a look at the cycling dynamic measurements. I've followed every rule and every direction, including trying several different firmware versions, and still, the readings are consistently low. I went so far as to do some math...maybe everyone else was wrong and Pioneer was correct, I thought, so I used some basic assumptions regarding tire and drive-train friction as well and wind resistance gleaned from actual research, and determined that there was no way I would have been able to move the mass of myself, my clothing, and my bike over x distance, over x time given the power output this device measured. Happily enough, the readings I received from my other meters lined up nicely. So...if you don't care much about your actual output, and are just looking for a way to measure and track comparative output...and you use nothing but the power meter, it's a cheap way to train with power. If you want *actual* numbers, however, you'll want to look elsewhere.