PowerPod Power Data

[iamthebadwolf]

Just got my PowerPod and the performed O&B calibration and since then used it for two rides. However, I'll appreciate it if could confirm the accuracy of the power data reported.
Below are my observations that have me a bit concerned/confused:
1. High fluctuation in power reading during ride whilst maintaining a steady cadence and "perceived effort" over certain sections. E.g. It could go from 270W down to 150W within the span of 3 seconds.
2. I've noticed a lag in the power reported during high intensity intervals most noticeable during sprints.
3. Although it has been windy recently where I live, the wind speed data from the ride has me concerned especially after I watched the video on "Fine-Tuning the PowerPod". Please advise.
4. I can't seem to be able to pair my heart rate monitor with the PowerPod. Do I need to reset the PowerPod to be able to pair a new sensor?
5. The value utilised for the aerodynamic drag defaults to 0.382 m^2. I'm curious if that is the correct value for me? I'm 6'-2" tall and my riding position varies depending on type of ride, i.e. for intense rides I'm usually on the hoods (elbows bent) or the drops while for less intense rides I'm in a more relaxed position that has me more upright. How big of an impact will these position have on the power recorded?

Lastly, I train with power extensively on my indoor trainer and want to ensure when riding/racing outdoors that the power numbers from the PowerPod are accurate. In would be no fun to think I'm in my "Tempo" zone only to realize I'm closer to "Threshold" and being dropped due to me over-cooking my myself to quick as I've done frequently when riding based on perceived exertion

Kindly find calibration rides and two rides I've used the PowerPod.

Your prompt response is much appreciated.

[Velocomp]

1. Power fluctuations are normal. Basically, what is happening is that environmental conditions (slope and wind) are changing constantly. PowerPod measures these changes second by second. Your body averages these changes by applying not responding instantly. If you want to see smoother watts, increase the smoothing factor on your bike computer.
2. This is the inverse effect of smoothing; the more you smooth, the longer the time delay. Don't worry; your PP ride file will record the changes instantaneously.
3. You are riding in a lot of headwinds/crosswinds/tailwinds. Wind speed fluctuations are normal
4. Wake up your HR strap and your other sensors too. Then do a new pairing
5. Your CdA looks correct for your height and weight. There is about a 5% difference between hoods and drops, though at lower bike speeds the 5% isn't as important. Note too that when you're climbing, CdA is not very important at all

If you've set up your PP correctly (and it looks like you have) then your indoor/outdoor numbers should be comparable, assuming your indoor trainer is accurate, which we cannot assess.

[iamthebadwolf]

Many thanks for the response. Few follow-up questions
1. I currently have the smoothing set to "dynamic". would you recommend modifying this setting?
2. How do i go about pairing new sensors? I've tried but it doesn't seem to pick up the HRM.

[Velocomp]

1. DPS is a good compromise between steady-state smoothness and high-responsiveness sprints. If you use this set your bike computer smoothing to 3 seconds or shorter.

2. Here is the process:

A. Wake up all your sensors
B. Confirm the sensors are awake by checking your bike computer screen. You should be able to see speed, cadence and heart rate
C. Press-hold the PP button for 4 seconds, until it starts flashing. It will pair to all your sensors, including HR

[iamthebadwolf]

Many thanks. A few extra questions/clarifications:

- I had to perform some repairs to my bike which required required me to flip it upside-down while the PP was still mounted (Note: no change to PP orientation on bike). The next day when I went for a ride the PP was reporting very low number for a while before it finally re-calibrated itself. Does this mean that the PP will have to be recalibrated whenever the bike (and PP) been held in a position other than its nominal orientation. e.g. would be affected if I had to lay the bike on side?

- Is there a battery level indicator within the Isaac software? Curious about the drain rate after a 3/4 hour ride and how often I need to re-charge I case if I forget prior to a ride.

- I recently changed my stem. do you think a new O&B calibration is required and how often would suggest recalibration of the PP to ensure current values are being used to report accurate Power readings.



Regards,

[Velocomp]

1. Likely your PP was bumped while the bike was upside down. It will recalibrate itself during the first 8 minutes of your next ride

2. No. I would recharge your unit once per week

3. Yes

[BBQcyclist]

Q/ Re. 'Rechaging once a week.'

What if my bike is in the garage from December to March? Do I still need to recharge the PP weekly, or can I let it go as-is and re-commence charging weekly next spring?

Thanks

[BBQcyclist]

?

[Velocomp]

I would recharge every other week. This will maximize long-term battery life.

[BBQcyclist]

Ok , will begin doing so today - thanks for this info.
Hope I didn't inadvertently decrease the battery life. Haven't recharged in over 6 weeks.