Suspecting calibration problems

[rhinocommuneer]

Hi! I've just purchased PowerPod v3 and now I'm trying to get reliable measurements.

Up to now, I've successfully setup PP on my handlebars, connected it to speed/cadence sensors, performed around 5 calibration rides (including one after installing Isaac for Mac). PP seems to work, it readily reports power, but I'm not satisfied with the accuracy. Also, I've noticed a number of discrepancies with instructions.

1. The status light does not quite behave as expected. For example, when pairing sensors, it indeed blinks while searching and triple-blinks red when connected to cadence. But there is no continuous glow when connected to speed. Similarly, during my first calibration ride, the light was blinking red/green, but since then it always blinks yellow.

2. The calibration rides are extremely short — the last one was barely 500 meters (although I've seen in Isaac something about 4 miles). Next, when reaching 50%, PP does not wait for me to stop and turn around — it just goes on. See an example of a calibration ride triggered by Isaac in the first 3 minutes of the attached ride.

3. Power numbers are frequently inconsistent with RPE. They look good on the climbs but don't do justice to the headwinds. To give you an objective marker, today I was pedaling fiercely on a descent while PP reported 0 power (see the attached ride around 19km marker). Overall I get pretty low average and normalized power (150-180W for FTP around 300W) while turning myself inside out.

I attach the TCX and IBR files for the mentioned ride.

[Velocomp]

You're correct that your calibration ride was not completed. I do not know why.

However, I was able to get a profile from your ride file. Profile and corrected ride file are attached. Load the corrected profile into your device and you should get good results.

Your HR signal looks very odd in your ride file; what kind of HR measurement are you using?

[rhinocommuneer]

Thanks, I will try this one.

Please disregard the HR reading, I believe it's because I did not wet the belt. Sometimes my Wahoo Tickr goes crazy like that.

I also have a question regarding the position of PP. There's a video for PP2 that teaches me to rotate it in the mount forward until stop. While instructions also teach me that it should look slightly down. Can you please elaborate on this in case of PP3? Should the mount itself be level and os on?

Is it allowed for something to touch the PP? I have cables going everywhere and one is currently touching the side of PP. It might be difficult to avoid this completely under all steering angles.

[Velocomp]

Thanks, I will try this one.

Please disregard the HR reading, I believe it's because I did not wet the belt. Sometimes my Wahoo Tickr goes crazy like that.

I also have a question regarding the position of PP. There's a video for PP2 that teaches me to rotate it in the mount forward until stop. While instructions also teach me that it should look slightly down. Can you please elaborate on this in case of PP3? Should the mount itself be level and os on?

Is it allowed for something to touch the PP? I have cables going everywhere and one is currently touching the side of PP. It might be difficult to avoid this completely under all steering angles.

1) PPV3 should be attached so that it "hits the stop" on the mount. This assures that the angle remains the same each time you attach PP to your mount.

2) For better performance in wet conditions, orient your mount so that PP points slightly down.

3) As long as your PP is rock-solid tight on the mount, and your cables are not obstructing the wind port, it should be OK if the cable touches lightly against PP.

[Velocomp]

Hi! I've just purchased PowerPod v3 and now I'm trying to get reliable measurements.

Up to now, I've successfully setup PP on my handlebars, connected it to speed/cadence sensors, performed around 5 calibration rides (including one after installing Isaac for Mac). PP seems to work, it readily reports power, but I'm not satisfied with the accuracy. Also, I've noticed a number of discrepancies with instructions.

1. The status light does not quite behave as expected. For example, when pairing sensors, it indeed blinks while searching and triple-blinks red when connected to cadence. But there is no continuous glow when connected to speed. Similarly, during my first calibration ride, the light was blinking red/green, but since then it always blinks yellow.

2. The calibration rides are extremely short — the last one was barely 500 meters (although I've seen in Isaac something about 4 miles). Next, when reaching 50%, PP does not wait for me to stop and turn around — it just goes on. See an example of a calibration ride triggered by Isaac in the first 3 minutes of the attached ride.

3. Power numbers are frequently inconsistent with RPE. They look good on the climbs but don't do justice to the headwinds. To give you an objective marker, today I was pedaling fiercely on a descent while PP reported 0 power (see the attached ride around 19km marker). Overall I get pretty low average and normalized power (150-180W for FTP around 300W) while turning myself inside out.

I attach the TCX and IBR files for the mentioned ride.

1) After the light flashed red/green, did you click the button to start the calibration ride? If so, are you saying that the watts climbed from 0 to 100 (1-2-3-4-5 etc) in only 500 meters? Are you also saying that, at the 50W mark, the light did not change to solid red?

I looked at your ride file in more detail. For the first 3 minutes of your ride your average bike speed was only about 8 mph, and you had several stretches where bike speed was about 5 mph. This is too slow for a valid calibration. Also, at these slow speeds the light won't turn red at the 50W mark; the light will continue to flash yellow.

I would do the following:

1) Attach PP to your bike.

2) Awaken your sensors

3) Press-hold PP button for 4 seconds, to do a new sensor pairing. This will put PP into calibration mode

4) Do a new calibration ride, making sure to keep speed above 20 km/h during the calibration.

Please post the results of your calibration ride.

[rhinocommuneer]

Hi John,

I just completed a ride according to your instructions.

1) After the light flashed red/green, did you click the button to start the calibration ride? If so, are you saying that the watts climbed from 0 to 100 (1-2-3-4-5 etc) in only 500 meters? Are you also saying that, at the 50W mark, the light did not change to solid red?

Not exactly. When pairing sensors, it indicates that cadence is found but I didn't notice it indicating speed (however it obviously does connect to speed sensor — otherwise there would be no wattage). After pairing sensors the light does not glow yellow, it switches off. Next, when I press the button, it turns on and glows yellow. It does enter red/green flashing mode neither if I ride or press button and then ride. Watts start climbing from 0 to 100 without stopping at 50 or turning red.

I made a video for you (as best as I could): https://www.dropbox.com/s/9j9679rk1tl37 ... 5.mp4?dl=0. I took care to move faster than 20 km/h and turned around ~60.

Next, the interesting part. I decided to do a reset (12 sec hold of a button) and start the calibration again. This time the light was blinking red/green, it turned red at 50 and seemed to complete the calibration just fine. I rode for about 15km getting reasonable readings of the watts.

Until the PP straight-up died. The watch was showing 0 watts, the PP did not react to button presses. I finished my ride, connected it to my laptop and tried to pair with Isaac. Nothing — until I held the button for 12 seconds again. Isaac congratulated me with completing the calibration ride. I don't know how to check the battery level of PP, but I charged it a day ago and it was laying on a table.

[rhinocommuneer]

Here are other files: full ride from my watch and a recording before losing PP

[Velocomp]

1) The end of any pairing sequence, before the light goes out, is a solid green light. Solid green means speed has been paired.

2) When the light goes out, if you click the button again it shows solid yellow. AFTER you start riding, about 10 seconds the light will flash red/green, indicating that PP is "armed" for calibration. Until you start riding, the light will not go to flashing red/green.

3) Your calibration looks fine

4) Restarting your PP with a 12 second press is like unplugging your computer while it is live. It hard-resets everything and puts PP back into an initial state. This is not recommended unless PP becomes completely unresponsive.

If you want to do a new calibration, press-hold for 4 sec, until light starts flashing. This does a new sensor scan and places your PP into calibration mode.

5) It is nearly impossible to tell what state your PP was in after your hard reset of 4). It does appear it went out but I can't tell why.

I can't tell from your video if the light was flashing red/green and if you clicked PP button while flashing red/green. It does not appear that you did; if not, you never started a cal ride. (your profile seems to have some default values in it).

I'm attaching calibration ride instructions so that there is 100% clarity about how to do it.

[rhinocommuneer]

Hi John,

Thanks for additional instructions. It would be great to get these in the box with the unit. The shortened version loses too much detail. An interactive app would be even better.

1) The end of any pairing sequence, before the light goes out, is a solid green light. Solid green means speed has been paired.

True, this is what happens, but you're contradicting the instructions — namely, 4c. I figured that the light should not go out after pairing. Am I reading it wrong?

5) It is nearly impossible to tell what state your PP was in after your hard reset of 4). It does appear it went out but I can't tell why.

I had to reset it because it seemed dead and was not recognized by Isaac. I will keep you posted if this happens again.

[Velocomp]

Hi John,

Thanks for additional instructions. It would be great to get these in the box with the unit. The shortened version loses too much detail. An interactive app would be even better.

1) The end of any pairing sequence, before the light goes out, is a solid green light. Solid green means speed has been paired.

True, this is what happens, but you're contradicting the instructions — namely, 4c. I figured that the light should not go out after pairing. Am I reading it wrong?

5) It is nearly impossible to tell what state your PP was in after your hard reset of 4). It does appear it went out but I can't tell why.

I had to reset it because it seemed dead and was not recognized by Isaac. I will keep you posted if this happens again.

After pairing process is completed the light does go out. This is what the instructions say:

4 " After pairing, click button. Successful pairing, light is solid yellow". This is correct...

Hopefully you won't have continued problems!