Sudden 0 watts during uphill

[itguy]

Hi, today while riding, I noticed 2 times that on my Garmin there is no power displayed, this is during uphill where i was trying to maintain 250w.

Attached below is the snapshot from Garmin:


It happened again at kilometer 58.99km but I am having trouble to upload the photo, I'll try to attach it later.

I have the .ibr file from PP if you can help to check if there is any problem with my PP.


Thanks

[itguy]

Here is a better reading of the graph

[Velocomp]

Please post the .ibr file.

[itguy]

Hi John,

Here it is:

[Velocomp]

My suspicion is that you are using a Garmin GSC-10 combined speed/cadence sensor.

In the places you show there are speed dropouts, which would force power to be zero. Since they are on uphills I'm guessing that your frame is flexing enough to cause the speed signal to become intermittent.

Make sure that your speed sensor/magnet are positioned properly.

If you continue to have this problem I suggest you get the new magnet less Garmin sensors, and place your speed sensor on the front hub. That will get rid of the flame flexing problem.

[itguy]

Hmm... I'm using Cervelo S3. I will try to adjust the sensor first, to see if it helps.

Also, I have exported the profile I am using, maybe this can help too?

[Velocomp]

This is definitely a sensor problem, not a profile problem.

[itguy]

Thanks John, I am going to try adjusting the sensor and then do a quick ride to see if the problem still persist, on a tough climb later.

[itguy]

Hi John,

I have adjusted the sensor and rode a out and back route today. The readings of the ride looks good so far.

Also, noticed you made a video in youtube about fine tuning the PP. I did that today and the numbers changed slightly.

Question: Is it ok for me to do this out and back ride often to help fine tune the PP more?

The route I rode today is basically couple of times per week and no issue on out and back, so by doing this more often, it will help to fine tune my PP to my bike and my profile?

Attached my profile and ride if you are interested to have a look at it!

[Velocomp]

This data looks great and there is no evidence of dropouts. Good job!

Certainly, you can periodically do an out-and-back ride to check calibration, but unless you see a major change I would leave things alone. Consistency is much more important than absolute accuracy.