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 "The 33"-Road Bike Racing We set this forum up for our members to discuss their experiences in either pro or amateur racing, whether they are the big races, or even the small backyard races. Don't forget to update all the members with your own race results.

11-07-13, 08:08 AM   #5126
waterrockets
Making a kilometer blurry

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Quote:
 Originally Posted by shovelhd The Powertap will estimate cadence because power cannot be calculated without it.
Powertaps actually use wheel speed for power calculations (torque * rad/s). Everything is done at the hub, so cadence is irrelevant to it.

It does estimate cadence for the display/recording of that value though, by detecting the torque pulse rate and running that through a quick internal algorithm (probably like pulse rate divided by two -- but there's got to be a bit more to it for edge cases).

11-07-13, 08:51 AM   #5127
ljrichar

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Quote:
 Originally Posted by aaronmcd Still getting used to the PowerTap. I have the Joule - is there a way to see average power without counting stoplights (when velocity = power = 0)?
You don't want to do that as it skews the results. Rest should be included in the overall picture. If you take those out, you are cheating your actual numbers.

11-07-13, 09:33 AM   #5128
echappist
fuggitivo solitario

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Quote:
 Originally Posted by ljrichar You don't want to do that as it skews the results. Rest should be included in the overall picture. If you take those out, you are cheating your actual numbers.
who the hell cares? you sound as if he were forging his tax returns. he's also not working at the intended power levels for a good 15-20 seconds for the time to slow to a stop and then revving it up again. And even if it does matter, it's not gonna change things by more than 1-2 watt...

to the OP, there's an option for stop recording when speed drops below a certain level. I know you can do this b/c i once had a Joule. If you can't get to the option, you could always call Saris.

as for the cadence, it's okay for 5-sec rolling average but worthless for application where you need accurate data (e.g. starting sprint rpm, etc)

Last edited by echappist; 11-07-13 at 09:37 AM.

 11-07-13, 09:49 AM #5129 rbart4506  You blink and it's gone.     Join Date: Mar 2005 Location: Dundas, Ontario Bikes: Race bike, training bike, go fast bike and a trainer slave. Posts: 4,436 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) That option would in include 0's when coasting then, which really is the goal when looking at average power/normalized power values... __________________ "On the other hand riding down a hill at 55 MPH wearing (essentially) women's underwear and a Styrofoam cup on your head is the epitome of rational life-extending decisions." - RacerEx
11-07-13, 11:03 AM   #5130
Racer Ex
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 Originally Posted by aaronmcd Just started using Power yesterday....Maybe it's that speed and feel mean more to me in how hard I should/can push at a particular point in my ride
I would suggest it takes more than a day to grasp the utility of a PM.

A power meter is there not to tell you how hard you can push. There's no blinking red and green lights. It's there to tell you how hard you did, to help you train in a way that will help you push harder, or to hit a target for a timed event.

How hard you should push in the last one is a number developed from analyzing PM data.

It takes time, data, and an understanding of training to make any use of a power meter. You will not suddenly be a better rider because you have one.

 11-07-13, 12:40 PM #5131 aaronmcd Senior Member     Join Date: Aug 2013 Location: SF Bay Area, CA Bikes: Cervelo S5 Posts: 3,089 Mentioned: 49 Post(s) Tagged: 0 Thread(s) Quoted: 389 Post(s) Another question. Today during morning commute, the Joule head unit would not display power. I tried pairing to no avail. Maybe the hub wasn't transmitting? I've only put about 100 miles on it so far. Any idea what to do? I don't imagine the battery is low unless it was shipped that way.
 11-08-13, 06:36 PM #5132 thechemist In the Pain Cave     Join Date: Mar 2008 Location: Nashville, TN Bikes: Posts: 1,669 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) Ugh, garmin vector won't work on my bike. Fine with going quarq but wife really liked the vector
11-08-13, 06:36 PM   #5133
mattm
**** that

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 Originally Posted by thechemist Ugh, garmin vector won't work on my bike. Fine with going quarq but wife really liked the vector
Why won't it work?
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11-08-13, 06:42 PM   #5134
thechemist
In the Pain Cave

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 Originally Posted by mattm Why won't it work?
"For a bike to be compatible with Vector, two critical areas need to be measured: (1) the crank and (2) the clearance between the crank and chain.
The cranks will need to be the proper thickness and height. Vector can work on cranks that are up to 15mm thick and 38mm in height."

Specialized fact and sworks are not compatible. It is frustrating as the convenience in swapping pedals between bikes is easy but your SOL on certain bikes. Garmin claims that they are working ona longer cable to help resolve this issue but I don't want to wait on what could be a very long time. I love the idea of pedal smoothness from the vector and left/right individual power given my recent injury but it just doesn't look like it will happen.

Edit: also you need 3mm between the Cain and frame in top gear. In my 52/11 I have 2mm, ideally garmin wants 5mm....come on garmin

 11-08-13, 07:20 PM #5135 Racer Ex  Resident Alien     Join Date: Jul 2007 Location: Location, location. Bikes: Posts: 12,998 Mentioned: 128 Post(s) Tagged: 0 Thread(s) Quoted: 297 Post(s) Piffle.
 11-08-13, 09:46 PM #5136 shovelhd Senior Member     Join Date: Jun 2010 Location: Western MA Bikes: Yes Posts: 15,669 Mentioned: 4 Post(s) Tagged: 0 Thread(s) Quoted: 9 Post(s) No ****. NRFPT.
 11-09-13, 06:35 PM #5137 globecanvas Ninny   Join Date: Jan 2010 Location: The Gunks Bikes: Posts: 5,294 Mentioned: 51 Post(s) Tagged: 0 Thread(s) Quoted: 686 Post(s) Sadly my Stages experience is turning into something of a saga... first the unit took on some water while on the roof rack in a rainstorm, which made it eat a battery a week. Leaving the battery compartment door off overnight and pointing a fan at it seemed to clear that up. A couple of weeks later I lost power halfway through a ride, when I got home I discovered the cause was the battery compartment door had popped off. Stages promptly mailed me two replacement doors. When I went to install one I discovered the reason why the door had popped off in the first place. The power meter unit is cracked along the edge of the battery compartment. Now I wonder if it was cracked before and I didn't notice, which could have caused the water problem. I expect they will send me a replacement with no trouble (they offered to replace the unit over the battery draining issue), and hopefully these are just teething pains of a new product. I haven't been without the use of the unit for even a day yet, and I'm still \$1k richer than if I'd bought another Quarq. But hopefully they will address these apparent design problems.
11-09-13, 07:39 PM   #5138
Racer Ex
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 Originally Posted by globecanvas I haven't been without the use of the unit for even a day yet, and I'm still \$1k richer than if I'd bought another Quarq. But hopefully they will address these apparent design problems.
My guess is that Vector won't have these kind of issues. It's been in beta testing forever; I think the time to market issues have been more about production.

Quarq's would drown (seem less prone to it now), Powertaps hate/hated wet weather. SRM's you could tape on a submarine and be fine.

Hope they get it sorted out for you. Had a long talk the other day with Hermes about cycling stuff in general. It's a passion based sport where companies can get away with making us their beta testers.

 11-09-13, 10:54 PM #5139 shovelhd Senior Member     Join Date: Jun 2010 Location: Western MA Bikes: Yes Posts: 15,669 Mentioned: 4 Post(s) Tagged: 0 Thread(s) Quoted: 9 Post(s) Microsoft has made us beta testers for decades.
11-10-13, 11:31 AM   #5140
mattm
**** that

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 Originally Posted by shovelhd Microsoft has made us beta testers for decades.
And other companies got it right the first time! lol

You'll be frightened to know the new big thing in software testing is "testing in production" - a fancy term for throwing it out there, seeing what happens, then fixing it on the fly; iterating a light-speed compared to the olden days.

Mostly applies to server-side stuff, but it will make you all alpha testers. It's a lot cheaper than paying someone to find the bugs and they don't even find them anyway..
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 11-10-13, 05:10 PM #5141 shovelhd Senior Member     Join Date: Jun 2010 Location: Western MA Bikes: Yes Posts: 15,669 Mentioned: 4 Post(s) Tagged: 0 Thread(s) Quoted: 9 Post(s) How do you load test a cloud app? You can't.
 11-10-13, 05:19 PM #5142 furiousferret Senior Member     Join Date: Jan 2006 Location: Redlands, CA Bikes: Posts: 4,874 Mentioned: 6 Post(s) Tagged: 0 Thread(s) Quoted: 209 Post(s) The current software design cycle came from Oracle in the mid 80's. DoD wanted a database to use and put up the requirements, which no one met. IBM (which was the industry leader at the time) told them they could not provide a product for a few years. Oracle told them they could provide it in a few months, which they did, but needed constant patching and service packs, changing the way software was provided. Prior to that releasing software with bugs was a no no. At least that's what one of my instructors told me. ------------------------------------------------------------------------- Just bought a Vector, the LBS made an offer I couldn't refuse. It should be here in a few days. Can't wait!
 11-10-13, 11:36 PM #5143 waterrockets  Making a kilometer blurry     Join Date: May 2006 Location: Austin (near TX) Bikes: rkwaki's porn collection Posts: 26,130 Mentioned: 2 Post(s) Tagged: 0 Thread(s) Quoted: 2 Post(s) You know what my current assignment requirements are? A video. Yep. Make it look like the video. I've tried fighting the good fight on this one, but I'm not getting any form of a requirements list. Luckily, I'm the right guy to make it look like the video. Am I surprised the healthcare exchanges weren't ready on time? Nope. We're both pulling money from the same pool. Last edited by waterrockets; 11-10-13 at 11:39 PM.
 11-11-13, 11:26 PM #5144 furiousferret Senior Member     Join Date: Jan 2006 Location: Redlands, CA Bikes: Posts: 4,874 Mentioned: 6 Post(s) Tagged: 0 Thread(s) Quoted: 209 Post(s) Bought Friel's Power Meter Handbook and Coggans Training and Racing with a Power Meter. No pictures and a bunch of graphs. Feels like I'm taking a class. Also, what the best software to use? Seems like most like WKO but Golden Cheetah and Race Day have their fans. I'm sure the answer is in here and I've been reading through, but there's a lot of noise between the content.
 11-12-13, 05:29 AM #5145 mike868y avatar by Sean Powers     Join Date: Jul 2008 Location: charm city Bikes: 2009 Specialized Tarmac Pro Posts: 9,212 Mentioned: 17 Post(s) Tagged: 0 Thread(s) Quoted: 205 Post(s) i don't know how much debate there is about wko being "the best," but GC is free.
 11-12-13, 06:27 AM #5146 globecanvas Ninny   Join Date: Jan 2010 Location: The Gunks Bikes: Posts: 5,294 Mentioned: 51 Post(s) Tagged: 0 Thread(s) Quoted: 686 Post(s) Stages did indeed ship me a replacement power meter the same day I reported the cracked unit. My company (audio recording/editing software) does public beta testing with a very fast turnaround cycle (sometimes we can push out fixes within minutes of a bug report). Mostly, users love it. Complex software will always have bugs, and corner cases get tested by production use in a way that no test suite can ever come close to. If you fix a user's bug within minutes of him reporting it, most of the time you have created a loyal customer.
 11-12-13, 07:00 AM #5147 valygrl Senior Member   Join Date: Jul 2003 Location: Boulder, CO Bikes: Posts: 8,546 Mentioned: 82 Post(s) Tagged: 0 Thread(s) Quoted: 162 Post(s) ^^ as someone on the other side of this use case, I disagree. If that happens once a year, sure, but if it happens 5x for each release, it just tells me the developer is too lazy to QC the product, and pisses me off. Plus when the bugs eff up my production data and exposes errors to my end users, it goes beyond annoying into the "searching for other software solutions" realm.
 11-12-13, 07:22 AM #5148 globecanvas Ninny   Join Date: Jan 2010 Location: The Gunks Bikes: Posts: 5,294 Mentioned: 51 Post(s) Tagged: 0 Thread(s) Quoted: 686 Post(s) In our case, the beta testing is public, but separate from release. Users choose to install the beta builds. Many of them do use the beta builds in production, though. It is very, very rare for a new bug to affect production data (in our case, the actual audio output of the program)... in fact I don't think that has ever happened.
 11-12-13, 07:34 AM #5149 johnybutts Senior Member     Join Date: May 2008 Location: Houston, TX Bikes: Type of horse. Posts: 3,312 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 6 Post(s) SRM installed and reading (not sure if it's calibrated). Just need the shop to recable the derailleurs today and I'll be out there riding with power shortly!
 11-12-13, 07:40 AM #5150 jsutkeepspining Banned.   Join Date: Dec 2010 Location: ohioland/right near hicville farmtown Bikes: Posts: 4,813 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) ^if you have a garmin or a pc7, you can check the calibration with a calibrated weight (take it to the post office or any shipping store). Takes all of 5-15 minutes.