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Old 09-10-17, 01:01 PM   #1
CanadianBiker32
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Power pod review power meter

What are your thoughts on this power meter for a date bike. To use off road and also in winter snow in cold temperature s. Like -20c. Etc


Power pod

Link is herr
https://m.probikekit.ca/cycling-power-meters/powerpod-powermeter-v2/11514777.html?affil=thggpsad&switchcurrency=CAD&shippingcountry=CA&thg_ppc_campaign=7170000001309292 6&gclid=CjwKCAjwos7NBRAWEiwAypNCe82e6Ft5rneU1bYwHaRLltnZQ9rkQ92hRQP1-VswLwKELy_VQ1iNtRoCUS8QAvD_BwE&gclsrc=aw.ds&dclid=CJv5zKyQmdYCFVe5TwodqGoO7Q


Thoughts? I know not as accurate as a crank or pedal.type..but to have it protected from off road stuff

Would.u think one could.get an idea of power out put with this device?
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Old 09-11-17, 10:01 AM   #2
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Very interesting. I want to know how accurate it is. If it's nearly as accurate as the other power meters, this could represent a big change in things.
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Old 09-11-17, 03:07 PM   #3
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That's not a power meter.

It's a wind sensor, and an algorithm. It's very much like Strava Power, with a little bit more info. It still doesn't know enough to actually get it right. Maybe it's 10 % off, maybe it's 100 %, you'll have no way of knowing.

For the same $400, you can get a direct force power meter from Stages or 4iiii. They'll be left-only, which means if you have an imbalance they'll be off by 2x that amount. But they actually measure power, and you can probably find a dual sided meter to use for a few minutes (like at the shop) to get an idea whether you have an imbalance and how to adjust the numbers if so. That won't be as accurate as a crank based meter, but it will be night and day better than a power pod.
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Old 09-12-17, 03:19 PM   #4
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Thanks
Quote:
Originally Posted by Seattle Forrest View Post
That's not a power meter.

It's a wind sensor, and an algorithm. It's very much like Strava Power, with a little bit more info. It still doesn't know enough to actually get it right. Maybe it's 10 % off, maybe it's 100 %, you'll have no way of knowing.

For the same $400, you can get a direct force power meter from Stages or 4iiii. They'll be left-only, which means if you have an imbalance they'll be off by 2x that amount. But they actually measure power, and you can probably find a dual sided meter to use for a few minutes (like at the shop) to get an idea whether you have an imbalance and how to adjust the numbers if so. That won't be as accurate as a crank based meter, but it will be night and day better than a power pod.
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Old 09-12-17, 08:41 PM   #5
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Old 09-13-17, 11:26 AM   #6
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Quote:
Originally Posted by Seattle Forrest View Post
That's not a power meter.
I think that you mean that it is not a strain gauge based power meter.

See this review here by DC Rainmaker
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Old 09-13-17, 12:05 PM   #7
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@gauvins

A meter is a device that measures something.

A power meter is a device that measures power.

This is NOT a device that measures power.

This is a device that measures wind.

Therefore, this is not a power meter.
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Old 09-13-17, 12:13 PM   #8
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Quote:
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@gauvins

A meter is a device that measures something.

A power meter is a device that measures power.

This is NOT a device that measures power.

This is a device that measures wind.

Therefore, this is not a power meter.
The powerpod estimates power in watts using a wind gauge. Other meters estimate power using strain gauges.

Some bathroom scales rely on springs. Others on strain gauges. Others on sliding weights as is commonly the case at your doctor's office.

What matters is the concordance (or lack of it) between instruments.
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Old 09-13-17, 12:27 PM   #9
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Power meters measure power, they don't estimate it. Let's not play semantics.

A PT has a maximum error of 1.5 %, what's the spec for the wind meter?
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Old 09-13-17, 01:22 PM   #10
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Quote:
Originally Posted by Seattle Forrest View Post
Power meters measure power, they don't estimate it. Let's not play semantics.

A PT has a maximum error of 1.5 %, what's the spec for the wind meter?
Please read DC Rainmaker review. Then we can argue if you feel like it
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Old 09-13-17, 01:25 PM   #11
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If the power inference that this thing makes is accurate, then I'll call it accurate. I think you're saying you expect it to be inaccurate, and you may have good reasons for saying it. But if it proves to be accurate, power meter is a good name for it.
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Old 09-14-17, 09:41 AM   #12
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Quote:
Originally Posted by Seattle Forrest View Post
A PT has a maximum error of 1.5 %, what's the spec for the wind meter?
Quote:
Originally Posted by gauvins View Post
Please read DC Rainmaker review. Then we can argue if you feel like it
I have, and didn't see an answer to my question. Apparently the thing can be 100 % wrong and it's still operating within spec. Because it's not measuring power.
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Old 09-14-17, 09:42 AM   #13
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Quote:
Originally Posted by noglider View Post
If the power inference that this thing makes is accurate, then I'll call it accurate. I think you're saying you expect it to be inaccurate, and you may have good reasons for saying it. But if it proves to be accurate, power meter is a good name for it.
The only way this thing is "accurate" is if we relax the definition of "accurate" very much.

Bottom line: Why would you pay $400 to get the wrong power numbers when Strava will give them to you for free or you could buy a legitimate power meter for the same $400?
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Old 09-14-17, 10:19 AM   #14
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Quote:
Originally Posted by Seattle Forrest View Post
The only way this thing is "accurate" is if we relax the definition of "accurate" very much.

Bottom line: Why would you pay $400 to get the wrong power numbers when Strava will give them to you for free or you could buy a legitimate power meter for the same $400?
I don't know much about these sensors and their usefulness for this application. Why do you expect this system to be inaccurate?

I'm not willing to pay even $400 for a power meter, but I like watching the progress of this stuff.
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Old 09-14-17, 10:43 AM   #15
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According to this review, the difference between powerPod and a Direct Force Power Meter is less than 2% on average, on rough roads (where powerPod is less accurate because estimating rolling friction becomes delicate).

So, 2% difference would be an upper bound, and it is not entirely clear that the reference DFPM is absolutely correct. If you look at other reviews, you'll see that the charts show several PM tracking closely but with some differences (measurement error).

---

I personally would not spend close to a thousand dollars for a power meter. I was lucky to get a used Stages (left crank only) for $200, and am happy with it. Otherwise, I would have seriously considered the PowerPod.

Note that the powerPod is a computer without display. It will record data, meaning that you do not have to ride with a computer (Garmin or other). The downside is that the battery is said to last 20h, so you'll have to recharge every few rides. (Stages runs on 2032 batteries and lasts something like 200hrs. I ride with a Bontrager Node 1.1 with battery life measured in months).

---

Final note: DFPMs, contrary to what the name implies, do not directly measure the rider's power. They measure the amount of tiny deflection in sensors. This deflection is used to infer how much pressure is applied on the metered instrument (pedal, crank, wheel, hub and such) and this amount of pressure is used to estimate the amount of watts produced by the rider. This is not trivial. For instance, in another review DC Rainmaker notes that most DFPM (at the time) lose accuracy with elevation changes (because elevation impacts temperature and pressure).

Last edited by gauvins; 09-14-17 at 11:30 AM.
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