"The 33"-Road Bike Racing - The real poop on Ergomo.

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View Full Version : The real poop on Ergomo.


Bob Dopolina
03-20-08, 11:54 AM
OK. I am an email away from dropping some coin on an Ergomo set-up (Pro with crankset). I needed some new hardware and ruled out PT and can't get a deal on SRM so it's Ergomo or nothing right now.

I would be getting the system at a great price and know I would get support so this is not an issue. My concern is about the reliability of the product itself. I live in the tropics so water is an issue. I know they have redone their computer and it has been improved.

Any advice, suggestions or anecdotal experiences from OWNERS of Ergomo systems would be greatly appreciated.


wfrogge
03-20-08, 11:57 AM
Pedal with one leg..... Egromo only measures one side :)

Bob Dopolina
03-20-08, 12:02 PM
Pedal with one leg..... Egromo only measures one side :)

Aren't the strain gauges on the SRM on the crank side? Isn't that one side?

If you are measuring the torsion on the axle then don't both legs apply torque to the BB axle?

Am I misunderstanding something?


El Diablo Rojo
03-20-08, 12:04 PM
OK. I am an email away from dropping some coin on an Ergomo set-up (Pro with crankset). I needed some new hardware and ruled out PT and can't get a deal on SRM so it's Ergomo or nothing right now.

I would be getting the system at a great price and know I would get support so this is not an issue. My concern is about the reliability of the product itself. I live in the tropics so water is an issue. I know they have redone their computer and it has been improved.

Any advice, suggestions or anecdotal experiences from OWNERS of Ergomo systems would be greatly appreciated.

I've got three and have had little trouble with them. I've also had PT's and they are no more or less problematic than the PT's. From what I've learned from SRM owners they about the same in the user issues.

Now here are the pro's and cons of owning an ergomo.

Pro's: accuracy (ignore the post about pedaling with one leg he knows not of what he speaks) i've tested this thing back to back with SRM's and it's within +/- 5w. Cost, compared to an SRM it's a pretty good deal. Altitude and gradient, you don't get that with an SRM.

Cons: Well it's really a ***** to move from one bike to the next. You can't use and external bearing BB with one. The new distributer Fit Multisport has not returned any phone calls or emails I've sent them. However ergomo Germany has been very helpful.


Personally I like it much more than my PT and for the money it's a better buy than an SRM.

curveship
03-20-08, 12:15 PM
Pro's: accuracy

The literature doesn't agree, or at least, gives very mixed reviews. Even if we accept that the Ergomo is properly installed and accurately measuring torque in the bottom bracket, it still assumes that the ratio of power between the left and right legs is constant. Studies show that, in fact, that ratio varies with intensity, fatigue and riding position.

wfrogge
03-20-08, 12:15 PM
Aren't the strain gauges on the SRM on the crank side? Isn't that one side?

If you are measuring the torsion on the axle then don't both legs apply torque to the BB axle?

Am I misunderstanding something?


Pretty sure the SRM does not measure just one leg like the Ergomo and since all things are not equal (for our legs) left leg power x 2 may give odd results though I admit it might not be an issue.

Another con to using Egromo is you are limited to the cranks you can use.

curveship
03-20-08, 12:16 PM
Aren't the strain gauges on the SRM on the crank side? Isn't that one side?

If you are measuring the torsion on the axle then don't both legs apply torque to the BB axle?

Am I misunderstanding something?

SRMs really measure torque in the chain. Both legs contribute to that. Ergomos only measure torque from the left side and assume that total torque is twice that.

El Diablo Rojo
03-20-08, 12:20 PM
The literature doesn't agree, or at least, gives very mixed reviews. Even if we accept that the Ergomo is properly installed and accurately measuring torque in the bottom bracket, it still assumes that the ratio of power between the left and right legs is constant. Studies show that, in fact, that ratio varies with intensity, fatigue and riding position.

Then you are misunderstanding how the ergomo interpolates the data. I had a Power Tap Pro for two years, looking at the data from the PT and the ergomo I've found no differences. I've done tests with both the PT and the ergomo on the bike and the data within a few watts of being the same. I've also done back to back tests with SRM's and egromos and found the same results. Racer X has had both (ergomo and SRM) and he has had the same results.

Phantoj
03-20-08, 12:21 PM
SRMs really measure torque in the chain.

More accurately, torque through the spider.

Actually, elongation due to bending of the arms of the spider.



What about something from Quarq instead of the Ergomo?

LT Intolerant
03-20-08, 12:23 PM
More reading for you but you may help w your decision...

http://www.cyclingforums.com/t443031.html
http://www.cyclingforums.com/t422842.html

wfrogge
03-20-08, 12:25 PM
Wouldnt BB flex account for some erroneous data issues when using it?

jrennie
03-20-08, 12:38 PM
Shouldn't since the ergomo is optical and not strain measuring device.

I think EDR and RacerEx can give you non-bias reviews since they have both used multiple power meters. From what I have read the ergomo accuracy is very sensitive to proper installation. As far as the device measuring only one leg, well it really depends on what you are trying to achieve. If you want to directly measure your readings to your friend PT or SRM it may be off but if you are using it to log and train then it doesn't matter if you device read 100w high as long as it is consistent in that reading.

My only gripe with the ergomo is the ugly head unit.

El Diablo Rojo
03-20-08, 12:44 PM
Shouldn't since the ergomo is optical and not strain measuring device.

I think EDR and RacerEx can give you non-bias reviews since they have both used multiple power meters. From what I have read the ergomo accuracy is very sensitive to proper installation. As far as the device measuring only one leg, well it really depends on what you are trying to achieve. If you want to directly measure your readings to your friend PT or SRM it may be off but if you are using it to log and train then it doesn't matter if you device read 100w high as long as it is consistent in that reading.

My only gripe with the ergomo is the ugly head unit.

This is the most important thing, as long as your data is repeatable then that is all that matters. FWIW I did like my PT I just like my ergomo better.

curveship
03-20-08, 01:02 PM
Then you are misunderstanding how the ergomo interpolates the data.

With all due respect, I'm not. The Ergomo makes an assumption about physiology: that the power differential b/w right and left legs stays constant. Studies say otherwise.

Check out the second link in LT Intolerant's post. There's also some stuff on biketechreview.com, but Kraig just redid the forum and I can't find the links. I'll post back if I can round them up.

Racer Ex
03-20-08, 04:12 PM
With all due respect, I'm not.

The due diligence is helpful, but seems heavily biased. For the record though, Ride magazine did a comparative review over several issues. They found it read higher in the higher (800+) wattages than the SRM or PT if memory serves.

I would ask if you've owned one? OP's not asking for a librarian or a human Goggle, but rather first hand user data, which you can't provide if you haven't lived with the units.

I did for nearly two years.

I no longer own one, I don't have any emotional attachment or financial interest. Here's my opinion:

I liked the computer on the Ergomo better than anything I've seen (I did paint it black though). TSS/IF, altitude, gradient, and cumulative feet climbed in an easy to use interface with big numbers for us elderly folks. I never had a weatherproofing problem but I never tested it as harshly as I have my SRM's. That said it saw sub zero and 100 plus temps, some water, snow and sleet. Never had an issue.

While absolute accuracy might be better with other units, compared to my SRM's I didn't see any wide discrepancies. Very good relative consistency, which is what you need in a meter that you'll be using as a training device. The one leg issue didn't manifest itself in any way, and given that I'm heavily left handed and footed, I'm not a bad test pilot.

The one thing to remember is that if you pedal backwards, you can make it read 8000 watts or so. Great for impressing BFer's, but it does throw your CP numbers off a bit.

It's also very light and gives you a choice of cranksets.

Installation is critical though. I do 99% of my own work, so I took time to make sure it was installed really well, and to the exact specs and orientation called for. A number of the problems people have had are a direct result of improper installation.

I ended up selling the units because I dropped the big bucks on a Dura style SRM (and later an FSA unit). I've got a number of bikes and the external BB bearing setup allows me to swap the SRM unit quickly and easily. I've got several bikes wired up and ready to go, something the Ergomo couldn't do.

Given my experience and needs I'd go with the Ergomo over any other powermeter except the SRM, as long as you are confident you can get it serviced. I had zero issues with either of my units.

Bob Dopolina
03-20-08, 05:49 PM
Thanks all for the input and the links. Big help.

Service won't be an issue as I am dealing with the Big Cheese from Germany (industry connection).

I run a Service Center, which is fully equipped, so I have the tools and the skill to install the unit correctly (at least I hope I do!).

+/- 5w is no biggie as long as it is consistent.

bdcheung
03-20-08, 06:30 PM
I'll echo RacerEx's comments 100%, sans the fact that I still own my Ergomo.

Pro Tip: I ended up putting teflon tape on the threads of my unit because the BB started squeaking.

ifox
03-20-08, 06:41 PM
What about intervals (laps) feature on Ergomo? I read somewhere that it's not available on Ergomo and intervals should be separated from each other using software.

bdcheung
03-20-08, 06:45 PM
Intervals are 100% present on the Ergomo headunit.

Mid-ride, hold down the bottom button for a couple seconds and it puts you in interval mode. Top button starts the interval, press again and it stops the interval, press again and it moves to the next interval.

The best thing is that in between intervals, you can use the bottom button to review average power/cadence/HR/speed from previous intervals.

ElJamoquio
03-20-08, 06:51 PM
The best thing is that in between intervals, you can use the bottom button to review average power/cadence/HR/speed from previous intervals.

You mean you review them the same way you can on a Powertap?

cslone
03-20-08, 07:23 PM
Then you are misunderstanding how the ergomo interpolates the data. I had a Power Tap Pro for two years, looking at the data from the PT and the ergomo I've found no differences. I've done tests with both the PT and the ergomo on the bike and the data within a few watts of being the same. I've also done back to back tests with SRM's and egromos and found the same results. Racer X has had both (ergomo and SRM) and he has had the same results.

No, it really does just double the power measured by the left leg. The bb doesn't twist on the right side, so it has to make the assumption that your right leg is putting out the same power as the left. Again, probably fine for repeatability, but can be off due to leg imbalances.
Although it would be nice to be able to use the race wheels without buying a new hub, a la PT.


http://www.saris.com/scienceofpower/2007ValidationErgomo.pdf

bdcheung
03-20-08, 07:34 PM
You mean you review them the same way you can on a Powertap?

In terms of basic functionality, yes, both units display data from previous intervals in the same way.

The Ergomo, on the other hand, allows you to exit "Interval Mode". The Powertap, by my experience, doesn't. Once you start an interval, you can't stop. You also can't stop one interval without immediately starting the next (i.e. on the PT, when you hold down both buttons to stop Interval1, Interval2 starts immediately). With the Ergomo, you can stop Interval1, recover, then start Interval2 at a later time.

El Diablo Rojo
03-20-08, 07:50 PM
No, it really does just double the power measured by the left leg. The bb doesn't twist on the right side, so it has to make the assumption that your right leg is putting out the same power as the left. Again, probably fine for repeatability, but can be off due to leg imbalances.
Although it would be nice to be able to use the race wheels without buying a new hub, a la PT.


http://www.saris.com/scienceofpower/2007ValidationErgomo.pdf

I understand how the ergo works, but the way that interprilates the data is more complex than just doubling the watts. That's why you do an offset prior to each ride.

I've done one legged drills and the watts are consistent on both legs. I had a PT wireless and did a complete workout with both the PT and ergomo attached. The two units were within +/- 5w. I really think everyone is making way too much out of the 'one side' thing.

ElJamoquio
03-20-08, 07:57 PM
The Ergomo, on the other hand, allows you to exit "Interval Mode". The Powertap, by my experience, doesn't. Once you start an interval, you can't stop. You also can't stop one interval without immediately starting the next (i.e. on the PT, when you hold down both buttons to stop Interval1, Interval2 starts immediately). With the Ergomo, you can stop Interval1, recover, then start Interval2 at a later time.

How is this a benefit?

Enthalpic
03-20-08, 08:26 PM
How is this a benefit?

+1

If anything this is a benefit as the recovery interval should be measured.

Dubbayoo
03-20-08, 09:39 PM
+1

If anything this is a benefit as the recovery interval should be measured.
I'll take a stab at it. Suppose your recovery is HR-based instead of time. I sometimes do intervals of x distance or n time and recover as long as it takes for my HR to drop to a certain level. My HR drops very slowly so the rest intervals can be long. Because the rest interval time varies I DO NOT want it included in the actual recorded time. I can see reasons for doing it both ways but it would just confuse me in that instance.

ifox
03-20-08, 11:51 PM
One more question. It seems that one would need Dura-Ace 7700 (or similar) crankset to use with Ergomo BB. DA is pretty stiff (for me, at least). What about Ergomo crankset? How is it compares to DA?

Bob Dopolina
03-21-08, 12:48 AM
One more question. It seems that one would need Dura-Ace 7700 (or similar) crankset to use with Ergomo BB. DA is pretty stiff (for me, at least). What about Ergomo crankset? How is it compares to DA?

Good question.

bdcheung
03-21-08, 04:44 AM
+1

If anything this is a benefit as the recovery interval should be measured.

Everything is recorded in interval mode, but when you download the data to WKO+ the intervals are marked as "Interval 1" and "Interval 2" and so on and so forth. The time between the intervals is still recorded and the data is still there, it just isn't shaded as an interval.

The Ergomo records continuously, sorry if there was a misunderstanding about that. "Interval Mode" simply allows you to mark off desired intervals. I don't consider my recovery an "interval" in the training sense. Nobody talks about doing 2x20's of rest.

Racer Ex
03-21-08, 07:50 AM
One more question. It seems that one would need Dura-Ace 7700 (or similar) crankset to use with Ergomo BB. DA is pretty stiff (for me, at least). What about Ergomo crankset? How is it compares to DA?

You have a choice on BB taper. ISIS, square taper Campy, Octalink, or ISO square. My first unit came with Campy, I used both the Ergomo crankset (compact) and a Record crankset. The Record was slightly stiffer, the Ergomo seemed fine (and came in standard 110 BCD vs. proprietary Campy).