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PostPosted: Fri Sep 25, 2009 9:07 pm 
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Has anyone heard when the Quard S975 for SRAM Red powerglide will be released?

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Posted: Fri Sep 25, 2009 9:07 pm 


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PostPosted: Sat Sep 26, 2009 12:25 am 
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This thread is turning wierd. If I buy an SRM-system (or any other PM for that matter) I would be pissed if it wasn't both accurate and consistent. After all, if I spend all that dough on a PM, I am serious about my cycling. If I'm serious, I would like to know how my numbers compare to others, right!? Hence, accuracy is important for such an expensive device. And obviously, if I would get different readings for the same input, how could I ever compare those readings to anything?


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PostPosted: Sat Sep 26, 2009 8:44 am 
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cornas wrote:
This thread is turning wierd. If I buy an SRM-system (or any other PM for that matter) I would be pissed if it wasn't both accurate and consistent. After all, if I spend all that dough on a PM, I am serious about my cycling. If I'm serious, I would like to know how my numbers compare to others, right!? Hence, accuracy is important for such an expensive device. And obviously, if I would get different readings for the same input, how could I ever compare those readings to anything?


I consider myself being serious about training, but i'm more interested in my numbers compared to my last year's numbers, don't care about other's numbers. There's always someone who's faster, so what the heck... So, while accuracy is important, consistency is crucial.


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PostPosted: Sat Sep 26, 2009 9:45 am 
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Totally agree.


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PostPosted: Sat Sep 26, 2009 9:59 am 
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Location: Aus
Me too!!!
So long as it is consistant and l am improving l'm happy.
I can climb local hills in a certain gear at a certain cadence and see that the reading is the same as it was 2 years ago + or - a few watts.


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PostPosted: Sat Sep 26, 2009 12:05 pm 
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spinwax wrote:
Couldn't a "new" PM company cut a lot of cost buy building a meter that has repeatability but not as accurate? Or do these have to go hand in hand?

If they create a PM with good repeatability all it takes to also make it accurate is a calibration in a test bench. The calibration can be done semi automatcally in the PM's software just by activating the calibrtion program while the PM is in the test bench. So it doesn't have to add any hardware costs to the PM. But of course you have to add a know reference load to the PM in the test bench to do the calibration, but they are probably going to test if it works anyway before packing it, so a calibration for accurancy wont add much cost.

Repeatability on the other hand is not something you can just calibrate the PM to obtain. To acheive good repeatability you have to make a good design with noise immunity and add compensation for things like temperature, ageing and maybe battery voltage. This all makes the device more expensive. Varitation over temperature is much bigger for electroninc sensing than most are aware of. So if no temperature compensation is added, measurements can vary quite a lot over temperature. And a bike can be expsosed to both very cold temperatures and very hot temperatures in direct sunlight.

You can save money by making a PM with poor repeatability that only shows the correct reading at at calibration temperature and while new. But you don't save that much by leaving out a calibration for accurancy.

It can be made possible for an end user to recalibrate the PM for accuracy himself by applying a reference load and pressing a button.


Weather proofing electronics with connectors, external sensors or replaceable batteries, to work in a bike eniroment is another thing that can be add a lot of cost.


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PostPosted: Sat Sep 26, 2009 12:56 pm 
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dual wrote:
cornas wrote:
...So, while accuracy is important, consistency is crucial.


If you have to replace your PM at some point do you want the replacement to produce different power numbers than your old PM?
If you decide to buy a second PM for another bike/wheel do you care if it produces different numbers than your first PM?
If you hire a coach who wants to compare your power numbers to other clients will he want your PM to produce numbers consistent with theirs?

I'd venture to guess that for most people accuracy is crucial.


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PostPosted: Sat Sep 26, 2009 1:12 pm 
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blaronn wrote:
dual wrote:
cornas wrote:
...So, while accuracy is important, consistency is crucial.


If you have to replace your PM at some point do you want the replacement to produce different power numbers than your old PM?
If you decide to buy a second PM for another bike/wheel do you care if it produces different numbers than your first PM?
If you hire a coach who wants to compare your power numbers to other clients will he want your PM to produce numbers consistent with theirs?

I'd venture to guess that for most people accuracy is crucial.


If you replace your PM with a PM of the same make, most likely any differences will be smaller than the differences in your sustainable power day to day, so hardly even noticeable. If you replace the PM with a PM of a different make, it is easy to account for any differences in output, e.g. PT against SRM...
I have indeed two PM's i train and race with (Powertaps). I keep any eye on their calibration routinely, so the above applies here as well. Differences between the two PT's are not noticeable, and (if they exist at all) definitely much smaller than the variance in my power day to day.
Why would a coach want to compare my numbers to anybody else's numbers? Makes no sense.
OTOH: When my PT tells me, that my FTP has improved by 50 watts during the last 12 months, i want that information to be absolutely reliable. For effective and successful training with a PM, it is really not necessary for the PM to be accurate down to a watt or two, but to be consistent, believe me.


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PostPosted: Sat Sep 26, 2009 5:30 pm 
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Francois_Viviers wrote:
In cycling magazine today, aparantly new powermeter. This time a pedal based powermeter, one on both sides, so measures bith legs independantly. Also supposed to be more affordable. Does annyone have any more info on this?

Please do share



Well there is another system that is more then 10 years old ,and it works independed right and left side,
the question was and is or people who got to work with it understand its potential

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PostPosted: Sun Sep 27, 2009 3:29 am 
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>> If you replace the PM with a PM of a different make,
>> it is easy to account for any differences in output,
>> e.g. PT against SRM...

What is your method for approaching this issue? I have a couple srm vs PT files and simple correction factors don't do it. There is also a potential issue of drift over time and user calibration.

I am very interested in this topic as I'm looking at running SRM on road and Quarq on TT next year. The SRM vs PT experiment was something I did on a whim as I had a wireless PT available and threw it on my SRM equiped bike to see what the differences were.


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PostPosted: Mon Mar 15, 2010 8:06 pm 
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Brim Brothers have made a new blog entry today. But there's not much news to tell, except that they will have some interesting news to tell in a month or two:
http://www.brimbrothers.com/2010/03/the-business-end
Barry from Brim Brothers wrote:
We hope to have a bunch of interesting hard information to give you in a month or two, but right now it’s hammer down 7 days a week in Brim Brothers (except for time off to go cycling). We know our technology is a winner. We’ve just got to get it to you.


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PostPosted: Mon Jul 26, 2010 5:47 pm 
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New blog update from Brim Brothers today: http://www.brimbrothers.com/2010/07/working-hard
Quote:
...Many people have contacted us asking about a launch date. Unfortunately there are too many unknowns to be specific right now, other than to say it will not be in 2010.


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PostPosted: Mon Jul 26, 2010 6:49 pm 
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Posts: 565
Does this mean they'll be returning their Interbike award for best new product, or whatever it was?

Love the picture they posted of the riders hitching a pull up the Tourmelet. Is that Schleck I see at the back?

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PostPosted: Tue Jul 27, 2010 9:53 am 
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worstshotever wrote:
Does this mean they'll be returning their Interbike award for best new product, or whatever it was?

What award are you talking about. AFAIK Brim Brothers have never displayed any product or pictures anywhere and therefore have never received any awards either.
Are you sure you are not thinking of another powermeter manufacturer? Maybe MetriGear? http://www.metrigear.com/products/
MetriGear was displayed at Interbike 2009, but I haven't heard about any awards they have won though: http://www.bikeradar.com/mtb/news/healt ... gear-23513
But there wasn't anything on display from BrimBrothers.

MetriGear was in Cyclingnews 2009 reader poll - Best new product, but didn't win: http://www.cyclingnews.com/editions/mtb ... ary-5-2010
Quote:
SRAM XX group: 3193
Garmin Edge 500 GPS computer: 2242
Zipp 303 carbon tubular wheels: 1597
Specialized Shiv time trial bike: 1399
Trek Speed Concept time trial bike: 1016
Metrigear Vector power meter: 845
Look/Time carbon blade pedals: 744
Giant Trinity Advanced SL time trial bike: 638
Scott Plasma 3 time trial bike: 548
Chris King Swift road hubs: 501
Reynolds RZR carbon tubular wheels: 467
Cannondale Flash carbon hardtail: 434
Storck Aero 2 time trial bike: 238
Cannondale Simon suspension fork: 208


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PostPosted: Tue Jul 27, 2010 4:01 pm 
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Joined: Sat Nov 28, 2009 10:07 pm
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You're right -- it was metrigear. I was sort of being tongue in cheek ... didn't mean to send you on a mission!

A couple weeks ago I was reading an old issue of Bicycling or some similar rag's coverage of Interbike, which featured a photo of the metrigear guys holding an award for most innovative product or something, and I thought, gee, with the advantage of hindsight I guess that was a bit premature wasn't it? Anyway, I'll look for the mag and see if I can close the loop on this later this evening.

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Posted: Tue Jul 27, 2010 4:01 pm 


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