MTM wrote:
rruff wrote:
MTM wrote:
I think they did, but I'm not that versed in Powertap offset values. I was wondering what one unit in the offset (as showed on my Garmin) corresponds to.
Looks like N-m if using Ant+.
https://www.powertap.com/...tes-to-offset-values If I'm reading that correctly each increment is 1 Nm (for both ANT+ and BLE, you just have a decimal point in the reporting value when using BLE). That's extremely blunt at ~10W for each step at 95rpm. Unless your powermeter is quite unstable, better not touch the zero offset at all if that is correct!
Just did 10 zero tests with my PT G3 with the dual ANT+ and BLE pod. On a Garmin I got 7 times the value -1 and 3 times -2. With the powertap app I got 7 times -0.12 Nm and 3 times -0.22 Nm displayed. Thus, I guess the ANT+ increment is 0.1 Nm i.e. -1 means -0.1 Nm.
With over 10 years experience with PT hubs, the zero setting always has been and still is a problem. Using auto zero in a TT is like gambling. In out and back courses sometimes I did 20 W more in the first leg, sometimes 15W more in the second leg, although it felt the same effortwise.
PT hubs have some plus points in aero testing but be careful with the zero setting, check it once and than don’t touch it again, the increment is just too large, and don‘t use auto zero!