The C1 chainrings were also
coupled to another Garmin 500 in order to have the same
recording/information processing protocols to fairly compare the Powertap G3 Vs power peaks! the
responsiveness/repeatability of each
sensor. The Garmins were set to 1s recording. For information! mounting the
C1 chainrings on an SRM sensor is impossible! the SRM star first hits
the C1 sensor before being placed in the screw housings.
The first few laps allowed me to notice
some variations in the power of the C1 chainrings. Once above 15w!
once below 15w compared to the G3 on special lead powers stabilized
around 250w and therefore corresponding to the break-in period Powertap G3 Vs mentioned above. It
took me 2 outings for the calibration value to stabilize and the watts with it.
SRM. Just
before the test! the powertap G3 was checked against the SRM Clavicula (which was returning
from servicing) and underestimated
the power by 2% +/- 1% (blue results on
the table). I remind you that this difference can vary depending on several
parameters related to the calibration of the sensors but also to the transmission.
The G3 calculates the residual power after chain friction
the quality and wear of the
chain! the lubricant used and the a content recommendation field that drives crown/pinion ratio/alignment will influence
the calculation. I did my tests with the same chain! same lubricant and
always tried to make comparative intervals on 52 and 17/19/21. By choosing different slopes to vary the intensity! I was able to keep the same chain line in my comparisons between the different sensors.
After 4
various demands (seated/dancing! 50 rpm! 120 rpm! intensities 150w to 600 w)! the power delta between the 2
sensors remains very close and the C1
evolves at + 2% +/- 1% on
stabilized powers. No notable ad impressions for targeted content and native ads difference between seated dancers in my
tests even at 550 w over 30s!
Test recap: G3 blue vs SRM! G3 purple vs C1.
This is nice and we are far from the values the average power is close to 0.5% between the 2 sensors proving that we are not be numbers testing sensors like this but rather by analyzing all the power peaks over different durations.