There is are both pedaling dynamics and gear ANT+ profiles. Why isn’t Shimano using these? If the pedaling dynamics profile is perceived to be deficient, then work with the standards group to enhance the profile.
gear profile? what is that? Here are the profiles:
I already answered why Shimano isn’t using the shifting profile:
Granted I wasn’t expecting them to take away access, but don’t think anyone was expecting that.
And already explained how the data is very different between the power meter data from the shimano crank and cycling dynamics. How do we know they aren’t in touch with the ANT+ Technical Working Group? Do you think a major change to the standard would be fast? The vectors are from 2013
and Garmin announced they wanted to get it into the standard in 2017
But the ant+ standard version of cycling dynamics came out in January 2019 (see the thisisant link above)
So kind of slow to change and Garmin went 6 years without following a standard…
Cycling dynamics is pretty simple for data in that its just 11 pieces of data over a base power meter.
for each leg:
- Start Angle
- End Angle
- Start Peak Angle
- End Peak Angle
and - Rider Position
- Right PCO
- Left PCO
So only needs 3 ant pages to send this data
Shimano’s power data is 49 pieces
for each leg for 12 positions around the cranks:
- angle
- power
and overall: - rider position
so 8-9 ant pages so easy to see how the data is very different and might even be hard to transmit that much data (the ant+ power meter spec only transmits ~8 pages a second for cycling dynamics data)
Gear was short hand for shift profile
Your explanation for my Shimano isn’t using the shift profile is blown out of the water by Shimano’s action. This is exactly why standards should be followed, so idiot corporations don’t hurt consumers.
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@GPLama Review of the Stages Dura-Ace R9200 DUAL Power Meter
Stages Dura-Ace R9200 DUAL Power Meter Review // This One Works!
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My jaw is dropping on the table as I am watching the video. What a trainwreck!
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I’ll share what I sent @dcrainmaker in private message: One could say they don’t seem to have the power to fix it.
Thank you, thank you, I’m here all night.
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The scariest thing? It’s consistently high on the small ring, it’s consistent in its behavior of showing positive power for a few seconds when cadence is zero, it’s nearly consistent in underestimating power in sprints: so it’s mostly consistent in its inaccuracies. Over the course of a longish ride, it’s almost certain that the average power you would observe would be close to the average you would have observed from a different power meter – it’s only when you drill down that you might see the problems.
This is why comparing the average power of two power meters over a ride is a very very low bar to meet. What’s important isn’t how close they are on aveage, what’s important is knowing when they’re different, and by how much. Most riders don’t bother to do all this work because it’s boring and they just want to ride – and they shouldn’t have to do all this work, and just riding is the goal we all have for how to use our time.
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That is about as devastating a review as I have ever seen from Ray…
What a total POS (the cranks, not Ray 
)
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The simple solution would be for someone to sue Shimano for false advertising as Shimano claims 1.5% or better accuracy.
@dcrainmaker’s review is even more scathing than @gplama’s. I’m really (negatively) surprised that Shimano’s last firmware update was from May 2022, i. e. they did not even attempt to at least mitigate some of the issues.
The second surprise is that the problem isn’t necessarily/only the crank arm design itself, but basically the whole package. They’d be better off just rebadging 4iiii power meters.
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Not surprised it sucks. Shimano has never demonstrated the ability that they can make a quality power meter
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Not yet. 4iiii really screwed the pooch with the Precision 3. It has taken them 12 months or more to dig themselves out of the hole of that hardware… with recent beta firmwares giving acceptable results. This is just the left side only though… which has been a solved problem for years now.
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Shimano can’t even design decent crank arms, lol
Makes me glad I have a p2m…
Doesn’t 4iiii also claim 1% accuracy even on single sided arms 
?
I mean, just the thought of a crank based PM at that accuracy is suspicious/hard to believe at best but on a single sided arm I just find it hilarious as for most people (me included) it simply means that the numbers produced are super accurate.
Back on topic, I also found funny how cadence seems to be an issue even though people are forced to use magnets 
Finally, I was interested in getting your thoughts on crank based PMs as to me they are only acceptable really as a budget solution and in the form of left side only.
Stages now seem to work LR, but would you really spend that much for a crank PM over a spider or a set of good PM pedals (speaking only in terms of quality of the data and leaving aside aesthetics etc)?
Didn’t you title your review video and article of the Stages DuraAce 9200 crank power meter with “This one works!”? I watched the video when you released the video, and going off vague memory here, I thought you were generally very happy with it. Or did I get that wrong?
Sorting out a crank / spider / rings / BB can be a PITA if you’re not across the compatibility/standards/etc. Removing a R8100/9200 crankset from a bike and swapping in a Stages LR R9200 is relatively straight forward. And there’s nothing like having everything on your bike meeting manufacturer spec… and not messing about with compromise using different chainlines/etc with a franken-spec setup. (Which a lot of teams at the TdU were happy riding…)
Related topic and something i’ve raised a few times: Shimano would be in a world of hurt if someone submitted their PM data/testing to the ACCC here in Australia showing their meter doesn’t match the spec as sold. I got a full refund on my R9200-P based on my testing… Retailers know it’s a POS. I just hope they’re putting pressure back on Shimano too.
You’re crossing streams here between 4iiii and Stages.
4iiii P3 Dumpsty: https://www.youtube.com/watch?v=MBSE04DNfAY
Stages LR R9200 Happiness: https://www.youtube.com/watch?v=H1YxXidWZc4
4iiii have mentioned seding over their LR solution soon. They asked if I wasted to test gravel or road… which was a sneaky for symmetry reasons… I requested both. 
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This doesn’t seem to be (only) a calibration issue. Ray and Shane are probably the best independent testers of power meters out there. They know where to poke and what possible causes are. From @dcrainmaker’s video I got the impression that the Shimano unit failed very basic tests that other power meters will generally just pass these days.
The two have lots of industry contact that can help them get to the bottom of things. I don’t see any indication Shimano has been in touch with them: Ray stated that he used the latest firmware from, hmmm, May 2022, i. e. no beta firmware. Shane first loaned a power crank from a bike shop for a day, and then bought one with his own money. It seems Shimano is still upset with him, when @gplama uncovered that all previous-gen Shimano crank-based dual sided power meters were inaccurate. (I find that quite childish.)
If it were a “calibration issue” like you say, this could be something that could be fixed over time. But it seems the issue is deeper. That’s a huge problem.
Two things: companies have to be willing to send pre-production gear to reviewers, and Shimano doesn’t seem to be. And I think it is worse if the problems are “limited to” customer units — that’s what you want to avoid in the first place!
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Yes, you are right, sorry about that.
PS I haven’t had luck with 4iiii a year ago either: I bought a refurb unit online, and the unit died after two weeks.
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