New powermeter rumours

Discuss light weight issues concerning road bikes & parts.
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djconnel
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by djconnel

jmilliron wrote:
asv wrote:DC Rainmaker has an in-depth review of the Stages Powermeter:

http://www.dcrainmaker.com/2013/01/stages-power-meter-in-depth-review.html


Ouch. This would be worthless to me in its current state. I'd want to use it to pace myself on climbs but the ones around here are not consistent. Lots of changes in grade due to switchbacks and whatnot.


Telling plot:

Image

So I agree. Wait for Stages-2.

by Weenie


commfire
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by commfire

Is the Vector project dead in the water?

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djconnel
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by djconnel

Not that I've heard about.

I guarantee, though, they wouldn't release with accuracy data like that.

An advantage small players like Stages have is they can afford to beta-test on users. Stages-1 will crash and burn, but they'll come out with a Stages-2 with two arm units and things will get better, I predict. Garmin doesn't have that luxury.

kervelo
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by kervelo

Is the Vector project dead in the water?


I hope not. Somebody mentioned somewhere that it would be released this spring, but I would not count on that.

kulivontot
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by kulivontot

djconnel wrote:
An advantage small players like Stages have is they can afford to beta-test on users. Stages-1 will crash and burn, but they'll come out with a Stages-2 with two arm units and things will get better, I predict. Garmin doesn't have that luxury.


Isn't it the complete opposite? Startups don't have the resources to absorb a failed product before releasing a second iteration. I agree that they can release a buggy product in limited quantities and it's better tolerated, and overall can take more risks, but the stakes for their first product are very high.

uraqt
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by uraqt

what I find kind interesting is that Stages, is sort of saying, and I admit that I am reaching.....

1. you can't prove that it's ours that is off
2. one power meter hooked up to two head units gets two different reading!!!!!!! This is not good for anybody if true!!!! 1st I have heard of this.( I wonder if this is why has taken garmin and brim so long to get to market) ( you have to give credit to quarq they were later than they said but they still delivered closer to their date than to garmin and brim)
3. it very very hard to get that 1.5 % accuracy.

DC's review is not good for Stages. I find it interesting that he is the only one that I have found that has "tested" it real world and not just reprinting the press day/ride they had in Boulder. Anybody have a different review with data? Ray is good but he can't the the single source when making a purchasing decisions. Even he calls out more than once and the 1st time in any of his reviews that i can remember is that it could be him and his use case. very very strange.

That being said, I think we have to given Stages a little time to
1. help us understand why Ray's data is they way that it is
2. updates to to their software. ( as everyones knows hardware easy , software very very hard.)
3. clean up their message. The reprinting the press day/ride they had in Boulder, have said multiple conflicting things, shipping dates, all the info on the Cannondale models and such.

C

commfire
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by commfire

Deleted

claus
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by claus

uraqt wrote:Anybody have a different review with data?


See RBR
One posting states:
... but Neal Henderson posted his data a few days later


Please check the posting for the links (TrainingPeaks data for Stages, SRM, and Powertap), there's also a follow-up about more information.

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djconnel
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by djconnel

uraqt wrote:what I find kind interesting is that Stages, is sort of saying, and I admit that I am reaching.....

1. you can't prove that it's ours that is off
2. one power meter hooked up to two head units gets two different reading!!!!!!! This is not good for anybody if true!!!! 1st I have heard of this.( I wonder if this is why has taken garmin and brim so long to get to market) ( you have to give credit to quarq they were later than they said but they still delivered closer to their date than to garmin and brim)
3. it very very hard to get that 1.5 % accuracy.


On #3 I fully agree: no power meter has 1.5% except maybe for Powertap (which has the drivetrain loss issue, and which loses precision as it ages). I state that with high confidence. The "constant cadence approximation" from using a magnetic cadence measurement that ticks once per revolution is enough to kill that.

On #1: that's the brilliance of the review. He calibrates to a LeMond trainer which since it uses big fat fans for resistance should be quite stable as a reference.

Image

At a given power the LeMond should be stable: constant LeMond power = constant power. It doesn't mean the ratio of powers on the LeMond is correct, so don't think because Quarq matches LeMond at one power it should match at all powers or the Quarq is wrong. For example, maybe LeMond models power proportional to speed to the 2.5 power, but it's more accurately speed to the 2.4 power. So focus on segments of near-constant LeMond power. The Quarq tracks the LeMond, but the Stages is all over the place.

Geoff
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by Geoff

djconnel wrote:...no power meter has 1.5% except maybe for Powertap...

And SRM, obviously...

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djconnel
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by djconnel

Geoff wrote:
djconnel wrote:...no power meter has 1.5% except maybe for Powertap...

And SRM, obviously...


No. It uses the constant cadence approximation. It's probably great if you hook it up to a motor. But when grinding up hills or through dirt I don't believe it's accurate.

deek
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by deek

djconnel wrote:On #3 I fully agree: no power meter has 1.5% except maybe for Powertap (which has the drivetrain loss issue, and which loses precision as it ages). I state that with high confidence. The "constant cadence approximation" from using a magnetic cadence measurement that ticks once per revolution is enough to kill that.

I always thought that the spider based powermeters included multiple hall effect sensors so that they could have a more accurate cadence reading throughout the pedal stroke.
Last edited by deek on Wed Jan 30, 2013 12:37 am, edited 2 times in total.

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cwdzoot
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by cwdzoot

Had the new SRAM ELSA come through the doors - here are some pics and actual weight for those who have not seen it.

Image

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Blog: http://glorycycles.blogspot.com/" onclick="window.open(this.href);return false;
Flickr: http://www.flickr.com/photos/glorycycles/" onclick="window.open(this.href);return false;

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prendrefeu
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by prendrefeu

Just to be clear, what is on the scale @ 508g?

Is it both arms, axle, quarq, rings? Anything else?

If that's truly only 508g, and the new pm design allows for easier ring swap... then someone could perhaps go:
ELSA compact + fibrelyte + non-sram GXP BB (such as Reset Racing) and be hovering around 600g ish?
If so... that's very, very impressive.

ELSA Compact PF30 + fibrelyte + PF30BB = damn light.

Less than an SRM?
Exp001 || Other projects in the works.

by Weenie


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HammerTime2
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by HammerTime2

What is included in that 508 g?

http://www.quarq.com/quarq-elsa-10r wrote:Weight 735g (GXP, 130BCD, 172.5mm)


If that 508 g is supposed to be for the whole enchilada, including BB, then as Southerners would say, that dog don't hunt.

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