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Lama down a rabbit hole

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So if you list to The Fit File podcast with DCRainmaker and our very own GPLama you will have heard the Lama mention being down a rabbit hole. Sounds like he struck the bottom and has published his findings. https://gplama.com/2019/06/29/shimano-crankset-power-meters/ 

So if you bought a Shimano based dual-sided power meter, could you return it under Australian consumer law as “not fit for purpose”?

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That's a grenade I didn't want to launch.... but had thought about. The ACCC would have a hard time proving what accuracy is though. And as Stages responded "we stand behind the accuracy and repeatability of the Stages Power R and Power L/R meters in the vast majority of use"... What defines 'majority of use'? Not ERG mode? In that case accuracy has to come with +/-%* 

Shimano Australia were happy to point the finger straight back at me. The detail is all in the post. And implies they had a steaming pile of shite power meter though to February this year!? What? I'll get a hold of another R9100-P and retest with the latest firmware one day soon. I won't be purchasing one for the task though. 

Hmmmm. Anyway. Be sure to check out Keith Wakeham's video on the topic. He worked for 4iiii inventing these things for years. He left prior to the R8000 and R9100 cranks coming along. 32mins long, but he peels back the layers for what's going on. And how it's a BIG problem.

This didn't get any airtime in the FIT File Podcast this week, I just touch on it at the end. I could talk for hours on this one - it's been a journey. And one that could result in a few interesting emails. 

Cheers for listening to the Podcast and reading my new website too.

 

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It was a great read and I enjoy the poddy, keep up the good work.

Shimano’s response is quite concerning and made me wonder if they had thought it through before sending.

It will be interesting to see how this all plays out.

 

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6 minutes ago, TimG said:

Here's an even deeper rabbit hole..

The 'why'.

 

And when you find out Keith's employment history and qualifications, the industry lets out a collective "Oh.... shit!" 

 

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I'm not smart enough for that video.

But from the first 5 minutes, do I assume all powermeter are crap and inaccurate?

 

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12 minutes ago, Peter said:

I'm not smart enough for that video.

But from the first 5 minutes, do I assume all powermeter are crap and inaccurate?

 

Nope. If I have it correct, it is the design of the ultegra and DA powermeters that makes them inaccurate. Basically, the cool looking spider f*&ks measurements up.

@gplama Did I get close? 

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8 minutes ago, TimG said:

 

@gplama Did I get close? 

Yep. They have to work hard to fudge up the numbers on the right to be accurate-ish for most riding conditions. ERG mode pulls the pants down and flicks the idea right on the balls. I had a suspicion of what was going on a while back. Companies kept replacing the cranks in the hope I had a dodgy product.... most sent two, some sent three. The eleventh (!) crank I rode last week, same tech, same Shimano spec, same issue.... so it's not any of the power meter companies (the 4iiii gauges on a more uniformly shaped FSA SL-K L/R crank was fine), it's the base unit that's flawed for the purpose they're using.

They're building houses on dirt, not concrete. 

I spent a few months trying to disprove my data. Trying to attack my findings. Trying to figure out where I screwed up. At the end of the day if you remove me from the picture, the issue remains. So it's bigger than just my data set. The power companies know this. Surely they've all thought about using their own cranks/design for a while now. 

I suspect I'm shitlisted now by most.... Let's see how it plays out. I'm trying to get a hold of more non Shimano power cranks/spiders/etc to throw though the Lama Lab Test. It's a pretty solid testing protocol. 

 

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