Pioneer ust announced on their Instagram that they will not be in cycling and cyling equipment including power meters any more.
Shimano is taking over all the cycling related products from Pioneer.
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finally shimano might have a working power meter !
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Always interested in this line of thinking. Just an anecdotal n=1, but my right side Stages Dura Ace has been flawless, so it’s obviously not impossible to pull off.
There is a big difference between getting consistent power reported (my guess on your results), vs getting ACCURATE reported power (what Shane is talking about).
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No, I know exactly what he is talking about. My two Stages L units, Tacx Neo, and R Stages are all within a percent and a half.
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I’m not disputing what you found, I’m just saying it’s obviously possible to make them work, mine does with no issues and I know several others who are the same. I’m more curious as to why a lot fail tbh.
This is actually what I was referring to with the line of thinking bit. You obviously can define it how you want for your purposes, but if an item works within its usage profile for its user, it hasn’t “failed”. Outside of that envelope is pretty irrelevant for someone who doesn’t need it. I understand for your purposes it you don’t feel it does but that clearly is a different proposition than it doesn’t work for anyone, which is what is bandied about all the time and I think is a ridiculous assertion.
As I mentioned, I’ve run mine with a L Stages and a Tacx Neo simultaneously and they have all tracked within 1.5%, which is good enough for me. Ray Maker has also had similar experiences while noting some people have issues. But some people aren’t able to get that obviously, which piques my interest.
I’ve seen the video by Keith, certainly informative but it still doesn’t really explain the inconsistency of manufacture.
The argument isn’t about inconsistencies when manufacturing power meters, but that power meters can’t be as accurate with this asymmetric crank arm design. On symmetric crank arms certain forces cancel (or are the same, which means their difference is zero) just by symmetry. Thus, offset and slope of the strain-to-force curve are more accurate on symmetric crank arm designs.
With Shimano’s asymmetric design, these forces do not automatically cancel, and playing with the curve worsens the accuracy of the offset and vice versa.
I think Shimano has its manufacturing down, and whatever tolerances you have can be taken into account during factory calibration — if Shimano had a good design.
The problem is a reminder why power meters will most likely be something that, for the most part, only groupset manufacturers will offer: to get an accurate crank-based power meter, crank design matters a great degree. (I think pedal-based power meters will have their place, too.)
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I have been using Pioneer power meter for 2-3 years and their headset for a year or so and I am quite happy with both.
i think they have a fantastic head unit. If you read the manual carefully, you will find out lots of good training screens. And I believe it has better screen layout than Garmin or Wahoo.
And yes, they have a chunky web site but when you play with it, it basically gives yo allt he information you need, surprisingly in very good way.
But lets see what Shimano will bring.
E
That’s really weird. The Neo notoriously reports low compared to other power meters. Consitently 15-25w based on the gear compared to my s-works power crank.
Other users have shared a similar experience on another thread with the assiomas and vector pedals.
I’m not going to get into it anymore as it’s not really germane to the thread but to say I’m a mechanical engineer by training (I ended up a yachtie and construction company owner by trade which is a whole different story) and I know the concepts used in strain gauges. Measuring on a asymmetric crank is not an impossibility.
When I talk about manufacturing, my WAG is that the metallurgy variation is probably a significant factor.
Any rate, its a thread for Pioneer being sold, so everyone carry on.
The issue is that the right crank geometry is very far from a straight beam, and thus the deformation-vs-relevant load relationship is both non-linear and load application dependent. The designer ends up making assumptions on the load application, and anything off those assumptions throws the measurements off.
This said, while there is certainly an imprecision in the measure, the real question is how relevant that becomes in real life. Is a +/- 2% power measurement detrimental to training and race performance compared to a +/- 1% measurement? At which point does the lack of precision translate into performance-significant impacts?
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My Pioneer L/R (gen 1?) had as many signal drops as my gen 1 Stages. Accuracy was good compared to my Drivo when there’s signal. So much happier with my Assioma Duo.
I’ve said it before. I love my single sided Pioneer PM. Got it brand new two years ago for like $360 and it’s had ZERO issues. I’m not surprised to read this though, Pioneer never seemed to gather a strong following or reputation in the PM world.
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Indeed, but this is more a function of inconsistent flexion across units, regardless of the load at the pedal axle (within reasonable parameters, no one is standing on the very edge of the pedal). Aluminum crank arms are the biggest wildcard in this, carbon could be built with much more precise deformation properties.
I don’t think that’s the case. The difficulty in a power meter is to calculate the load normal to the crankarm line, and eliminate the flexion/compression alongside the arm. While that’s easy for a set of strain gauges on a straight beam, it becomes a lot more difficult when dealing with a hollow part with a complex shape and integrated chainring attachment points like the recent Shimano crankset. So the errors come from the incorrect separation of pedaling forces between contributing (i.e. normal to the arm) and non-contributing (alongside the arm). The distribution of these two components changes quite a lot between riders, cadence ranges, and standing vs seating pedaling.
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I mean, it is, you are describing it in the following sentences. We use strain gauges in yachts that are worlds more complex than a simple power meter. But the properties and flexion/deformation across any load profile are very precise and known in advance.
At any rate, this probable could use it’s own thread.
Can we move the crank discussion to a separate thread and keep this to the original topic?
I can push them into a new thread, or leave that to someone else to start, and I can migrate the related posts as needed.
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I’m done anyway.