Callibration ride in WINDY conditions?

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djaustin
Posts: 31
Joined: Sat Apr 23, 2016 3:52 pm

Callibration ride in WINDY conditions?

Post by djaustin »

I moved my second PP to my TT bike and conducted a calibration ride. this was a closed circuit (so not out and back), but there was a very strong side wind - such that I couldn't always stay on the aerobars! PP was calibrated and I rode for another few laps that looked reasonable. Today I rode a 25 mile TT on heart rate to look at my PP Watts, and Normalised Power is reported as 335 Watts. Based on my road racing experience, this seems about 10% too high, although I have not formally tested FTP yet (hence the TT).

Can you comment on
1) The calibration - should it be out and back or just keep going (I did wonder when it stuck at 50W, and it took ages, possibly due to the wind!)
2) The first post calibration ride - these numbers look reasonable for the five (windy) laps I rode of a course I know very well, based on RPE
3) The 25 mile TT, again in windy conditions; coasting was identified correctly at the turnarounds

Mount is your combined Garmin/PP TT dual mount (and very nice it is too), bike is a 9 kg, steel TT bike, reasonable aero position that is UCI legal, and held for the entirety of the rides, aero helmet, skinsuit with shoe covers. Tyres are very low resistance Vittoria Corsa Speed Tubeless 23c at 7 bar, which were measured as having the lowest rolling resistance of any tested tyre. Rider is 68 kg.

Last question, can I pair my heart rate monitor now the profile is set? If so how do I do this? It failed to find it, but my other PP did. Same for cadence, although this appears unnecessary from my experience.

Many thanks.
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Velocomp
Velocomp CEO
Posts: 7963
Joined: Fri Jan 11, 2008 8:43 am

Re: Callibration ride in WINDY conditions?

Post by Velocomp »

I don't see anything in your setup that looks wrong. You may be a stronger rider than you think!

Yes, you can add your HR strap by doing another scan. This won't affect your calibration results.

Your cadence data is missing, too. If you're using a magnet-less cadence sensor ride around a bit before pairing. My experience is that these kinds of cadence sensors don't wake up immediately.
John Hamann
djaustin
Posts: 31
Joined: Sat Apr 23, 2016 3:52 pm

Re: Callibration ride in WINDY conditions?

Post by djaustin »

Thank you.

I'm happy to try a less windy calibration, but wanted to confirm that "out and back" could be riding around a closed circuit. I didn't think to turn around and ride the circuit counter-clockwise!

The two units are in reasonable agreement, but I didn't want to swap the unit off the TT bike. The second unit is for "road bikes", which are all largely the same (position is identical, weight within 2 kg, tyres all 25c high quality clinchers). I just swap unit and speed sensor.

And this gives an FTP of 320, which is higher than I expected but not impossible. I don't worry about absolute numbers, just consistency between bikes for training efforts.
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