Tyre size in active profile

[stavrosd2006]

Being using aeropod, with road bike having both tyres sized 700x28c.
Tyres had to be replaced due to max wear, and i decided to install, aft tyre 700x28c, front tyre 700x25c. Garmin speed sensor, is installed on front hub.
My tyre size in active profile is set for 700x28 tyre, do i need to change it?

If yes, what should be the value?

Stavros

[Velocomp]

There is a very minor 1.5% difference in tire circumference between the two tires.

This will not result in significant changes in power measurement, but you can change the profile if you wish. If you do so do a new cal ride after changing the profile.

[stavrosd2006]

So, to clarify, tyre size where speed sensor is positioned, should be altered in aeropod settings?
e.g. in my configuration, 25c is what i should select and not 28c, correct?

thank you.

Stavros

[Velocomp]

So, to clarify, tyre size where speed sensor is positioned, should be altered in aeropod settings?
e.g. in my configuration, 25c is what i should select and not 28c, correct?

thank you.

Stavros

Correct

[stavrosd2006]

So, to clarify, tyre size where speed sensor is positioned, should be altered in aeropod settings?
e.g. in my configuration, 25c is what i should select and not 28c, correct?

thank you.

Stavros

Correct

Cheers!

[ChrisW]

Would it be better to use measured tire size rather than that written on the sidewall. I'm sure everyone has noticed that on the same wheel, one model of tire labeled as "25c" tire can measure 24mm wide and another "25c" can be almost 28mm wide. If measuring, is it tire width that's important or tire height above the rim, because those also normally differ significantly.

Or are a couple of mm's difference not important for CdA testing and we can just use the manufacturer's stated size without the need to measure? Thanks.

[Velocomp]

The variable that is important is the circumference of the tire. We use tire size tables to determine circumference.

If you want you can manually measure and then enter the circumference into the profile.