I'll preface by saying I've been using PP for about 6 months and am the whole pretty pleased with it. An unexpected benefit was the indoor trainer feature: the virtual power curve on the PP matches the Kurt Kinetic inRide sensor very well; the Garmin Edge 520 gets both indoor and outdoor data from PP and that means I have both in Garmin's Connect, solving a problem with TrainerRoad, which still has no way to import outdoor rides (although otherwise I love TR).
My question is just what the header says. I already know that PP will use 8 minutes to recalibrate if it gets "confused" about something, and that the watts during those 8 minutes are junk data. It doesn't do that 8 minute ritual on every single ride however -- and that's always welcome. I want to know exactly what conditions trigger the ritual so that I'm not inadvertently triggering it by something I'm doing -- e.g. repositioning the unit on the bike. One example: I store my bike hanging vertically from a hook. I stopped doing so on the conclusion of a ride because the radical change in orientation while still the PP was still on seemed to result in 8 minutes of recalibration the next day. Same with even cleaning up the bike.
Leaving the bike strictly alone for 20 minutes until PP turns itself on (no other way) is not far from superstitious behavior. I would rather know exactly what conditions trigger the recalibration than just guess on the basis of strange numbers the next day. Thanks.
What triggers 8 minute recalibration?
Re: What triggers 8 minute recalibration?
The exact answer to your question is: nothing triggers the recalibration. This is because PP is checking its calibration 100% of the time, whenever there is non-zero bike speed
Any time the speed sensor is sending non-zero bike speed, PP is recalibrating itself. So, for example, if you've got your bike on a bike stand after a bike ride, and you're cleaning the bike, spinning the crank, PP will think you are climbing (or descending) a huge hill. This will disrupt the tilt calibration constant and screw up the first 8 minutes of your next ride.
There are three ways to deal with this:
1) At the end of the bike ride, remove PP from your bike and locate it remotely from your bike, so that PP won't pick up erroneous speed sensor signals.
2) If you're using a magnet less speed sensor, remove the wheel from your bike so that you
3) At the end of a ride, wait 20 minutes so that PP goes to sleep. After that you can move the bike and speed sensors around any way you want...
Any time the speed sensor is sending non-zero bike speed, PP is recalibrating itself. So, for example, if you've got your bike on a bike stand after a bike ride, and you're cleaning the bike, spinning the crank, PP will think you are climbing (or descending) a huge hill. This will disrupt the tilt calibration constant and screw up the first 8 minutes of your next ride.
There are three ways to deal with this:
1) At the end of the bike ride, remove PP from your bike and locate it remotely from your bike, so that PP won't pick up erroneous speed sensor signals.
2) If you're using a magnet less speed sensor, remove the wheel from your bike so that you
3) At the end of a ride, wait 20 minutes so that PP goes to sleep. After that you can move the bike and speed sensors around any way you want...
John Hamann
Re: What triggers 8 minute recalibration?
Does connecting it to a PC and downloading rides with Isaac help reduce that 20 minutes between bikes issue? Or does one just have to manually force which profile with isaac to do that.
Re: What triggers 8 minute recalibration?
Connecting to a PC and downloading will reset the ride file.
John Hamann
Re: What triggers 8 minute recalibration?
Thanks, John. You're quick.
Learning that it's a non-zero speed signal that keeps the PP awake and digesting info suggests one more workaround if, like mine, your speed sensor is magnetic: just loosen the spoke magnet and slide it up the spoke. Easier in my case than taking off the PP. Or does the cadence sensor also keep it chugging?
Either way, seems like in the next edition of PP a simple on-off function would eliminate all these guess-and-golly workarounds to avoid a possible maximum 20 + 8 minute penalty if you fail to guess PP's quirks.
It's off-topic but I want to add that Isaac, a bit off-putting on first acquaintance, provides amazing slices and dices of information when you know how to find and read them. If it were a food processor, you'd be rich!
Learning that it's a non-zero speed signal that keeps the PP awake and digesting info suggests one more workaround if, like mine, your speed sensor is magnetic: just loosen the spoke magnet and slide it up the spoke. Easier in my case than taking off the PP. Or does the cadence sensor also keep it chugging?
Either way, seems like in the next edition of PP a simple on-off function would eliminate all these guess-and-golly workarounds to avoid a possible maximum 20 + 8 minute penalty if you fail to guess PP's quirks.
It's off-topic but I want to add that Isaac, a bit off-putting on first acquaintance, provides amazing slices and dices of information when you know how to find and read them. If it were a food processor, you'd be rich!
Re: What triggers 8 minute recalibration?
I'm not 100% positive but I think that moving the magnet (so speed = 0) will let the PP go to sleep.
Adding more functions is tempting, but our experience is that every time we do something to add more user control, a reasonable percentage of customers have problems. Simple is hard...
Thanks for your comments about Isaac. We know it's intimidating at first, but we agree that the effort pays off handsomely!
Adding more functions is tempting, but our experience is that every time we do something to add more user control, a reasonable percentage of customers have problems. Simple is hard...
Thanks for your comments about Isaac. We know it's intimidating at first, but we agree that the effort pays off handsomely!
John Hamann
Re: What triggers 8 minute recalibration?
I have a question about that 8 minute calibration too.
Just to understand how things work.
Does PP change the profile after this calibration? When I should somehow how change the angle of the mount a little PP will calibrate at the start of the next ride.
But will it do that again on a 2nd ride? Or should it be fine on that ride? If I make sure I don't tilt the bike at the end of the ride or while cleaning. (I understand it will calibrate, but if there is nothing to change the numbers should be fine from the start)
I had moved the mount a little and didn't force a calibration ride again. On all rides PP would show very high or low numbers for the first 8 minutes. But after a forced calibration ride the numbers in the first minutes look a lot better.
To me that looks like PP is starting from the loaded profile a calibrates for the moved mount instead of calibrating ones a starting of from there on the next ride.
But maybe it has to do with moving the bike after the ride or cleaning. To get to where I store my bike I have to get up a couple of stairs.
I will make sure I won't trigger the speedsensor while moving the bike upstairs now. Never thought about the before.
Just to understand how things work.
Does PP change the profile after this calibration? When I should somehow how change the angle of the mount a little PP will calibrate at the start of the next ride.
But will it do that again on a 2nd ride? Or should it be fine on that ride? If I make sure I don't tilt the bike at the end of the ride or while cleaning. (I understand it will calibrate, but if there is nothing to change the numbers should be fine from the start)
I had moved the mount a little and didn't force a calibration ride again. On all rides PP would show very high or low numbers for the first 8 minutes. But after a forced calibration ride the numbers in the first minutes look a lot better.
To me that looks like PP is starting from the loaded profile a calibrates for the moved mount instead of calibrating ones a starting of from there on the next ride.
But maybe it has to do with moving the bike after the ride or cleaning. To get to where I store my bike I have to get up a couple of stairs.
I will make sure I won't trigger the speedsensor while moving the bike upstairs now. Never thought about the before.
Re: What triggers 8 minute recalibration?
PowerPod CONTINUOUSLY recalibrates itself during a ride.Rob_B wrote:I have a question about that 8 minute calibration too.
Just to understand how things work.
Does PP change the profile after this calibration? When I should somehow how change the angle of the mount a little PP will calibrate at the start of the next ride.
But will it do that again on a 2nd ride? Or should it be fine on that ride? If I make sure I don't tilt the bike at the end of the ride or while cleaning. (I understand it will calibrate, but if there is nothing to change the numbers should be fine from the start)
I had moved the mount a little and didn't force a calibration ride again. On all rides PP would show very high or low numbers for the first 8 minutes. But after a forced calibration ride the numbers in the first minutes look a lot better.
To me that looks like PP is starting from the loaded profile a calibrates for the moved mount instead of calibrating ones a starting of from there on the next ride.
But maybe it has to do with moving the bike after the ride or cleaning. To get to where I store my bike I have to get up a couple of stairs.
I will make sure I won't trigger the speedsensor while moving the bike upstairs now. Never thought about the before.
At the beginning of a new ride, particularly if the PowerPod has been reattached to its mount, any large errors in angle will take 8 minutes to fully self-correct. There is nothing you have to do to initiate the recalibration.
Yes, if you spin the wheel after your bike ride ends, as you might when cleaning the bike or moving it upstairs, PP will "think" you're still riding and will try to self correct for the odd angle of the bike stand or stairs. So, if you can do so, don't let the wheel with the speed sensor spin during bike stand work.
John Hamann
Re: What triggers 8 minute recalibration?
So that means if I just adjusted the PP on my handle bar, the first ride it was re-calibrating itself for 8mins.
After that, for any subsequent rides, if i do not adjust it anymore, the PP will work like normal, is this correct?
After that, for any subsequent rides, if i do not adjust it anymore, the PP will work like normal, is this correct?
Re: What triggers 8 minute recalibration?
PowerPod automatically checks its angle continuously at every point of every ride.
If you've installed PowerPod according to the instructions, so that it can't rotate in its mount, then after the first calibration ride it will provide "normal" readings at all times.
PowerPod readings will be affected whenever its angle relative to ground changes. Here are some things that can cause PowerPod's angle with respect to ground to change:
1) PP is not fastened tightly into the mount. You hit a bump and the PP rotates, or you push on its button and it rotates
2) You remove PP from its mount, then reattach the PP to its mount afterwards. When you reattach it, you do not place it at exactly the same angle where it was attached previously.
3) One of your bike tires starts losing pressure during the ride, causing the angle of the bike to shift slightly (yes, this has happened to us)
4) You install the PP mount "backwards", so that tightening the GoPro screw has no effect on clamping the PP tightly into the mount. Thus, the PP can rotate freely in its mount, even when the screw is fully tightened (yes, this happens too).
PowerPod does not know if or when any of these conditions occur. So, it continuously checks angle and makes any required adjustments. If you've followed the instructions then none of the above conditions exist, and you'll get "normal" readings all of the time.
If you've installed PowerPod according to the instructions, so that it can't rotate in its mount, then after the first calibration ride it will provide "normal" readings at all times.
PowerPod readings will be affected whenever its angle relative to ground changes. Here are some things that can cause PowerPod's angle with respect to ground to change:
1) PP is not fastened tightly into the mount. You hit a bump and the PP rotates, or you push on its button and it rotates
2) You remove PP from its mount, then reattach the PP to its mount afterwards. When you reattach it, you do not place it at exactly the same angle where it was attached previously.
3) One of your bike tires starts losing pressure during the ride, causing the angle of the bike to shift slightly (yes, this has happened to us)
4) You install the PP mount "backwards", so that tightening the GoPro screw has no effect on clamping the PP tightly into the mount. Thus, the PP can rotate freely in its mount, even when the screw is fully tightened (yes, this happens too).
PowerPod does not know if or when any of these conditions occur. So, it continuously checks angle and makes any required adjustments. If you've followed the instructions then none of the above conditions exist, and you'll get "normal" readings all of the time.
John Hamann