Login required to started new threads

Login required to post replies

Prev Next
Which power meter to get?
Quote | Reply
Hi All,

I'm going to get serious about training for next year and need to add a power meter, I've been planning on putting a 2.4sl in my 404 but would like a bottom bracket setup but don't really want to lose my durace/q-ring setup. Are there really any differences besides factory support?

Please help me spend money.
thanx,
chris.

Chris Bailey
Jupiter, Fla
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
Ergomo............
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
I think the key question you need to ask yourself is if you want something that is very easily swappable between bikes. If you want to quickly and easily move your powermeter from one bike to another, then a Powertap 2.4 SL is awesome. If you only plan on using one bike with the powermeter, then an Ergomo or a SRM could also be a good choice (although some folks with SRMs say that swapping cranks between bikes is also pretty easy, although I would think merely swapping rear wheels would be a little simpler). Finally, most folks would probably say that the gold standard in current powermeter technology is the SRM crankset. Personally, I have been very happy with my Zipp 417 rim with Powertap 2.4 SL setup for racing and training. Here's some pics:
http://forum.slowtwitch.com/...MLP%20steed;#1383243

Spot

___________________________________________________
Taco cat spelled backwards is....taco cat.
Quote Reply
Re: Which power meter to get? [trvfsub2] [ In reply to ]
Quote | Reply
...but then I need to gt rid of my durace stuff, right? Is a bottom bracket setup that much more accurate than a power tap?

Chris Bailey
Jupiter, Fla
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
Accuracy is a huge HOT topic, price not sure i got the ERGOMO carbon cranks that go with and then ordered the campy Q-rings to match. Love the set-up.............

tfun~
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
I can't speak to the accuracy of the Ergomo vs Powerap, but the reliability of the Ergomo seems to be superior. Powertaps dying in the rain seems to be a very common complaint. There are also complaints about the reliability of the Ergomo, but most seem to be a result of improper installation. If you face and chase the bottom bracket shell, pay attention to the installation instructions, and calibrate properly, the Ergomo should be very reliable. Is your Dura-Ace setup 9 or 10 sp? If 9, you can use it with the Ergomo (order the Octalink BB). If 10sp, it won't work with the Ergomo.
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
In Reply To:
...but then I need to gt rid of my durace stuff, right? Is a bottom bracket setup that much more accurate than a power tap?

How much are you willing to spend and will you be installing it yourself?

BTW, it's been said before that if one had to choose a power meter to be accurate "straight out of the box", the winner would be a PT. Most other PMs are more sensitive to installation/calibration issues to get good numbers (that includes SRM.)

My recommendation would be that instead of listening to some random inputs from an internet forum, get yourself a copy of Allen and Coggan's "Training and Racing with a Power Meter". The price of the book is worth it alone just for the chapter that compares and contrasts the various PM options.

http://bikeblather.blogspot.com/
Quote Reply
Re: Which power meter to get? [Tom A.] [ In reply to ]
Quote | Reply
Better yet ... ask AC to send you a signed copy and in return you will agree with everything he says on Slowtwitch. ;)
Dave
Quote Reply
Re: Which power meter to get? [dcsxtri10] [ In reply to ]
Quote | Reply
In Reply To:
Better yet ... ask AC to send you a signed copy and in return you will agree with everything he says on Slowtwitch. ;)
Dave

You aren't referring to me, I hope. I'll have you know that I got my copy through Amazon and the only person who "signed" it was me, when I put my name in the front cover to make sure I get it back from all the friends who borrow it from me! Harrumphhhh!

Besides...I've "corrected" the good doctor on ST on more than one occasion (although admittedly it's typically on some minor quibble ;-)

http://bikeblather.blogspot.com/
Quote Reply
Re: Which power meter to get? [Tom A.] [ In reply to ]
Quote | Reply
Actually I was referring to thunderball .... but I enjoyed your response! He wouldn't even give you one??? ;-p
Dave
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
In Reply To:
Powertaps dying in the rain seems to be a very common complaint.

They've resolved this with the newer models.

But I'd go with the Ergomo if I had to do it over again. I have the PT now so can't use it with my race wheels.
Cam
Quote Reply
Re: Which power meter to get? [cray] [ In reply to ]
Quote | Reply
Thanx guys, I appreciate all the opinions. I would bet that this year there are going to be a whole new array of pm on the market to feed the new need.

I want a pm I can use on race day with my disc but maybe if it's windy I'll use my 404 so I guess maybe that answers my own question and a powerap ) is not practicle even though it's half the price and super easy to start out using. Reliability on the new models is good but then it's new so who knows. That book is on my short list of things to learn on training with watts.

Chris Bailey
Jupiter, Fla
Quote Reply
Re: Which power meter to get? [thunderball] [ In reply to ]
Quote | Reply
I'm truly surprised by all the positive Ergomo reviews - perhaps the people recommending them don't actually own them? The reviews from Ergomo customers that I know have been almost universally negative.

The good news is that if you really want an Ergomo, you should have no trouble finding one used, and at a good price relative to retail. In fact, I know several people looking to offload ergomos so that they can purchase SRM or Powertap units...



.



.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply
Re: Which power meter to get? [fredly] [ In reply to ]
Quote | Reply
I can't speak for others but I do own one- in fact I've owned two (I sold my previous one when I took a little "break" from triathlon, and bought a new one a while ago). I've never had a single issue with either one. What sort of problems have you heard about?
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
I agree, I have not have any issues with my Ergomo. I think it works very good.
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
"What sort of problems have you heard about? "

1- the darn things don't work (at least for a significant number of people.) Metering power from one leg, and doubling it, is extremely problematic if you want accurate and consistent results.

2 - I live in Seattle, and putting a $1000 bottom bracket in a bicycle just doesn't work when you typically need to replace your bottom bracket at least once a season, and oftentimes more frequently.


.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply
Re: Which power meter to get? [fredly] [ In reply to ]
Quote | Reply
In Reply To:
2 - I live in Seattle,

In Reply To:
you typically need to replace your bottom bracket at least once a season, and oftentimes more frequently.

Are these two statements connected in some way? How?

Count me in as another positive Ergomo user.
Quote Reply
Re: Which power meter to get? [fredly] [ In reply to ]
Quote | Reply
Have you actually used an Ergomo?

1) Unless someone has some wierd severe leg strength discrepancy, I've never seen any data to support your statement that either accuracy or consistency is impacted in any measurable way. I'd love to see what data you have.

2) The Ergomo has 4 seals protecting the innards. I really doubt that even Seattle weather would cause you to have to rebuild the BB any more frequently than you have to service an SRM.
Quote Reply
Re: Which power meter to get? [Greg66] [ In reply to ]
Quote | Reply
"Are these two statements connected in some way? How? "


Take a look at an annual precipitation map.


Here's a question; how many happy Ergomo users have used another brand of Power meter? How many have tried putting an Ergomo and PT on the bike at the same time?

I had a training client with both a PT and an Ergomo, and after comparing the data sets side by side, the Ergomo got sold. Fast. (and yeah, it was installed correctly, and seemed to work perfectly well up until the point that it's data was actually compared to a known accurate standard...)

Hey, I'm an Ergomo dealer; I would love it if these things were better, but they just aren't.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply
Re: Which power meter to get? [Greg66] [ In reply to ]
Quote | Reply
Greg: I think he's saying that he replaces the BB because he rides in 9-10 months of rain and wet weather.

BTW, I live on the other side of the Cascades, where we get 9-10 months of sun, and I LOVE my Ergomo. Not one problem in 7 months. And I find the data to be very accurate.
Quote Reply
Re: Which power meter to get? [fredly] [ In reply to ]
Quote | Reply
Have you seen this?

http://mywebpage.netscape.com/...rgomo/ergomo-pt.html

"The Ergomo appears to produce wattage numbers quite consistent with that of the Power Tap. The Ergomo's cadence measurements appear to be over-smoothed, but this should matter only to those who are interested in further analysis of their data. This analysis does not compare features, usability, or reliability -- it only examines the quality of the power data. The evidence from this limited sample of data (i.e., 1 ride from 1 rider) is that consistency of power measurement doesn't appear to be an issue to worry about; a tentative conclusion might be that you should base a purchasing decision among power meters on features, usability, reliability, and price rather than on the method of measuring power."


Note that this compares the older Ergomo Sport, which only had a 5 second sampling rate, to the Powertap Pro. if anything, the new Ergomo Pro that can do 1 sec sampling would be even better, and would have totally fixed the "oversmoothing" issue. If your client was seeing drastically different data between the two systems, something was wrong with one of the systems.
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
"1) Unless someone has some wierd severe leg strength discrepancy, I've never seen any data to support your statement that either accuracy or consistency is impacted in any measurable way."

Take a look, there's plenty of it out there, and it doesn't take a "severe... discrepancy" to skew the data, at least from the n=1 that I had data for.

"2) The Ergomo has 4 seals protecting the innards. I really doubt that even Seattle weather would cause you to have to rebuild the BB any more frequently than you have to service an SRM. "

From what I have seen, you would be wrong in that asessment, and you don't "rebuild" an Ergomo BB, you replace it. They are pretty good with warranty service, but even if they warranty the unit, you are without a BB and a PM for the period of time necessary to get this done. PITA at best.


.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply
Re: Which power meter to get? [fredly] [ In reply to ]
Quote | Reply
"Take a look, there's plenty of it out there, and it doesn't take a "severe... discrepancy" to skew the data, at least from the n=1 that I had data for."

Really? You mind pointing me to one? I just referenced one pretty detailed comparison that showed no discrepancy at all.

"and you don't "rebuild" an Ergomo BB, you replace it. They are pretty good with warranty service, but even if they warranty the unit, you are without a BB and a PM for the period of time necessary to get this done. PITA at best."

How is that any different than being out your SRM while it's being rebuilt? I've got plenty of spare $40 BB's laying around. I'd rather be out a BB than a set of cranks or a wheel.
Last edited by: jkatsoudas: Oct 2, 07 16:28
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
"The evidence from this limited sample of data (i.e., 1 ride from 1 rider)"

'nuff said.

"Note that this compares the older Ergomo Sport, which only had a 5 second sampling rate, to the Powertap Pro. if anything, the new Ergomo Pro that can do 1 sec sampling would be even better,"

Not for the data set in question.

"If your client was seeing drastically different data between the two systems, something was wrong with one of the systems. "

Agreed. What was "wrong" was that the Ergomo was incapable of actually metering the rider's wattage output, rather than metering half the riders output, and doubling it.

It's pretty darn simple; the Ergomo doesn't actually meter output, it meters half of it, and guesses at the rest. There are credible reports (other than mine) of this being problematic for certain riders. Why buy a unit that may or may not work, based on a problematic (even if merely theoretically, for you, maybe, you will probably never know...) method of data collection?


.


.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply
Re: Which power meter to get? [jkatsoudas] [ In reply to ]
Quote | Reply
"How is that any different than being out your SRM while it's being rebuilt? I've got plenty of spare $40 BB's laying around. I'd rather be out a BB than a set of cranks or a wheel."

Well, it's different for a number of reasons:

1) SRMs (essentially) never fail, and if they do, they mail you a replacement overnight.

2) I can service my SRM myself, so it never has to go back.


.

Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/
Quote Reply

Prev Next