PT Zero Torque & Temp

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Hi,

It's a hot summer where I am - upto 45 deg C / 113 deg F so I'm alternating between outdoor and indoor riding. It seems when I go from a zeroed torque indoors on the Powertap (20 deg C/ 68 deg F) to outdoors it can take about 5 zero procedures to get the power right (it's too high initally) and similarly the same the other way (too low and see lots of -0).

Is it normal to take a few zero procedures with such extreme temperature changes?

Hi,

It's a hot summer where I am - upto 45 deg C / 113 deg F so I'm alternating between outdoor and indoor riding. It seems when I go from a zeroed torque indoors on the Powertap (20 deg C/ 68 deg F) to outdoors it can take about 5 zero procedures to get the power right (it's too high initally) and similarly the same the other way (too low and see lots of -0).

Is it normal to take a few zero procedures with such extreme temperature changes?
How much time between zero procedures - are you doing it right after you go outside?

I'm not sure how normal it is, but it's not surprising with such a big temp change.

If possible, leave the bike, or at least the wheel, out to adjust for a half hour.

If you have the auto-zero turned on, it should adjust automatically if you coast periodically. Just keep in mind that it won't auto-zero if it's off by more than 7 in-lbs, so definitely manually zero before you start.