New powermeter rumours

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goodboyr
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by goodboyr

Lol. Don't hold your breath....."coming soon".....

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toiyuet
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by toiyuet

The "new" battery inside only last 1900 hors, the rechargable model only last 100 hours.

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itsacarr
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by itsacarr

I agree - regardless of who they licensed \ partnered \ or co branded with the technology adds some solid functionality to the platform. I would certainly look forward to having a PM I can migrate between frames or new bikes and not have to worry too much about standards. It's also nice to see the weight come down (because ... ww). As for the battery life, the rechargeable isn't much less than the replaceable battery PM's and nice I suppose not to have to buy the watch batteries. I think the quarqs are rated at what, 200 hours now?

The new chainrings also shift fine with 9070 so I wouldn't consider the update if it lands with the 9100 rings to be an issue.

Beyond all this, while I have seen 2 or 3 working versions of the origin crankset in person, availability is always an issue. At least in the states. We shall see I guess.

Either way it's nice to see SRM making some steps forward in an ever increasing competitive market these days.
Just ride ..

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mai
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by mai

Pioneer SGY-PM910V (current gen) on FC-R9100 (170mm, 50-34)
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Pioneer SGY-PM910H (2 gens old) on FC-6800 (170mm, 50-34)
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jay cee
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by jay cee

New Shimano PowerMeter
https://youtu.be/okNpp5_E2-4
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urart
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by urart


maquisard
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by maquisard

No secret the Easton powermeter is OEMed by the Team Zwatt guys. Looks good.

maquisard
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by maquisard

http://road.cc/content/tech-news/221643 ... -%C2%A3250

I remain slightly cynical about a lot of these very cheap single sided crank mounted powermeters, particularly those that are bonded to the crank at home by the customer. From an electronics instrumentation point of view, making a powermeter is not difficult. Productising it, and the design for manufacture side of things, is difficult.

Looking forward to reading the reviews of this one as I am from a rowing background and this cycling powermeter crankset is derived from a rowing based powermeter.

goodboyr
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by goodboyr

LAN wrote:First of all, just let me say, I am not a SRM fanboy. Actually I just purchased a Quarq DZero Red, and I have never owned a SRM

But SRM just announced a very light product, and you don´t believe it. This forum is not the comment section on road.cc or Bikeradar, we should be able to look past the adjectives used in the announcements or press releases from those sites. What´s left is a lighter powermeter than Quarq.

It´s hard to compare the weight 100% with the information available but it is easy to conclude that the weight is WITH chainrings.

Dura-Ace crank arms (left): 175g
SRM crank arms: 99g
Difference: 76g

If we assume that the right crank arm have a similar difference, the arms are 152g lighter.

DA SRM weight: 768g
lighter arms: -152g

That leaves 616g, and then we can assume that the 30mm aluminium spindle used by the new crankset is lighter than the Shimano steel spindle. If the chainrings are not included in the weight, the aluminium spindle must be over 100g heavier that the steel spindle, highly unlikely.


Thinking back to this discussion.....I guess it wasn't real after all.

ichobi
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by ichobi

This might be of interest to many of you here


Huge scientific study shows inaccuracies of popular power meters By Cycling Weekly.

Here's the relevant bit.

Screen Shot 2560-05-13 at 9.30.58 AM.jpg

Screen Shot 2560-05-13 at 9.31.14 AM.jpg


Trueness we probably don't care too much. But precision within each unit shows some interesting picture.

hogehoge
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by hogehoge

Why do the power meters on the right hand side of the Stages have so few data points?

ichobi wrote:This might be of interest to many of you here


Huge scientific study shows inaccuracies of popular power meters By Cycling Weekly.

Here's the relevant bit.

Screen Shot 2560-05-13 at 9.30.58 AM.jpg
Screen Shot 2560-05-13 at 9.31.14 AM.jpg

Trueness we probably don't care too much. But precision within each unit shows some interesting picture.

TurboKoo
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by TurboKoo

Quick question regarding Garmin Vectors: how is the repeatability on high watts? I feel like I'm inline with my ftp, L/R balance but while sprinting I've done new records when compared to SRM and especially to Stages.
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ichobi
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by ichobi

If you wanna read the fullpaper see here: https://www.dropbox.com/s/q95lsk8za0paw ... 5.pdf?dl=0

maquisard
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by maquisard

Stages comes off particularly badly.

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ichobi
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by ichobi

The researcher acknowledged this however:

"This comparison, however, is not completely legitimate because the power meters from Stages calibrated in this study measured only torque in the left crank arm, with the assumption of the right side being equal. Thus, the derived trueness and precision in the current study always depended on the power meter itself and the riding style of the cyclist (left-right balance). A varying left-right balance during the calibration would increase the variability of the measured power outputs and, therefore, lower the precision. Kirkland et al. [16] reported a contribution of 48.9 ± 3.6 % from the left leg in a group of 9 competitive cyclists for similar power out- puts. The variability of 3.6 % illustrates how the accuracy of the Stages power meter could be strongly in uenced by the cyclist him- self, apart from technical measurement error."

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