"The 33"-Road Bike Racing - Fluid 2 Trainer - Power Numbers

Hey,

I'm wondering what I should make of this. I've been riding with my new Ergomo for a little now. The numbers seem accurate to me. Yet, when compared against published power numbers for the Cycleops Fluid2, there is a discrepancy.

According to the chart here, http://curveship.dyndns.org/cgi-bin/aah/trainerpower.pl , at 17 mph I should be putting out 242. I was spinning at about 17.5 - 18 mph at my endurance heart rate. And that was, according to my Ergomo, about 190-200 watts. That number seems about right, considering my outdoor endurance pace and other online calculators. I was also able to spin at my heart rate LT, at about 20mph. That would be 388 watts...so something is wrong. I'm not that strong.

So there are two possibilities as I see it. The first, is that my endurance wattage is around 260-270, and my Ergomo is way off. Considering I weigh around 140, that would be phenomenal and thus likely wrong. So, there is option two (more likely I guess), that something is way off with my cycleops fluid 2. It would seem to be putting out a lot less resistance than it should be.

The ride stats were NP = 196 watts, speed at around 17. I'd be interested in hearing what people think.

[edit] I should add that I played around with the tightness of the resistance unit against my tire, which was fully inflated, and was unable to replicate the numbers even closely.

something is way off with my cycleops fluid 2 [estimations].


You already know your answer.

As I just finished a trainer ride(fluid2) with my power tap and I must be a monster because I average 21mph for a little over an hour. I am going pro with 460 watt average :rolleyes: I think the calculator might be just a little off

[edit] I should add that I played around with the tightness of the resistance unit against my tire, which was fully inflated, and was unable to replicate the numbers even closely.

Don't overtighten it against the wheel...you don't get anymore "resistance" that way.

As I just finished a trainer ride(fluid2) with my power tap and I must be a monster because I average 21mph for a little over an hour. I am going pro with 460 watt average :rolleyes: I think the calculator might be just a little off

That's moving right along on a Fluid 2....

That's moving right along on a Fluid 2....

+1. My Fluid2 seems to require more power than a level road at any given speed.

Yep. After about 5 minutes of 21 mph, my legs start to ask if I'm done yet.

Although when my first resistance unit started leaking, it got progressively easier :D

I'm on my 3rd resistance unit, BTW.

I have found this to be fairly accurate once the Fluid2 warms up:

http://www.foosoftware.com/g2photodata/gallery2/d/3978-1/Fluid2_power.jpg

^That chart seems awful optomistic. According to it, I can maintain 750W for 1min, and 400W for over an hour.

Good news is if you keep your Ergomo properly calibrated, you don't have to care about speed on the trainer anymore :)

Here are some numbers from my PowerTap and Fluid2:

Speed.................Wattage
15.5...................94
16.5...................115
17.9...................141
20.4...................253
21.3...................277
24.5...................389

just checked the PT file:
avg speed avg cadence avg power
20.72 102 211

I think something must be messed up then

I'm pretty confused now. It seems everyone gets different power numbers from their Fluid 2. For reference, I was spinning in my 53/21 at around 95 rpm, so according to that chart, I'm a beast. At first I was worried about my Ergomo's calibration, but now I'm a bit concerned about my Fluid2.

What's interesting about the chart that I posted, is that at the low end, like at 13 mph, the numbers are spot on (about 112 watts). It's when my speed is increased, that my power numbers fail to increase as the chart predicts. But at least intuitively, my Ergomo seems more right than the Fluid 2. Well, as long as it isn't leaking fluid, I'll just ignore the speed. But I have a feeling that could be sooner, rather than later.

Here are some numbers from my PowerTap and Fluid2:

Speed.................Wattage
15.5...................94
16.5...................115
17.9...................141
20.4...................253
21.3...................277
24.5...................389


I am really close to this with my KK and PT.

I'm pretty confused now. It seems everyone gets different power numbers from their Fluid 2. For reference, I was spinning in my 53/21 at around 95 rpm, so according to that chart, I'm a beast. At first I was worried about my Ergomo's calibration, but now I'm a bit concerned about my Fluid2.

What's interesting about the chart that I posted, is that at the low end, like at 13 mph, the numbers are spot on (about 112 watts). It's when my speed is increased, that my power numbers fail to increase as the chart predicts. But at least intuitively, my Ergomo seems more right than the Fluid 2. Well, as long as it isn't leaking fluid, I'll just ignore the speed. But I have a feeling that could be sooner, rather than later.
The different power numbers might be due to variations in how tight people have the wheel up against the drum.

FWIW, cycleops has the powercurves for their trainers up on their website.

I wasn't able to find a powercurve on the Saris website, but I found this one, which is quite different than the others. http://www.1upusa.com/1uptrainerpowercurves.htm .

I'm just going to stop worrying. Though it would be nice to get my Ergomo independently checked for calibration.

I wasn't able to find a powercurve on the Saris website, but I found this one, which is quite different than the others. http://www.1upusa.com/1uptrainerpowercurves.htm .

I'm just going to stop worrying. Though it would be nice to get my Ergomo independently checked for calibration.

Wow! Thanks for posting that - I never knew that the 1up could be configured like that. The Fluid2 is great but I can never get to do real SEs on it where I need to put out about 400w at 50 rpm. I can never get the resistance that high to get down into those low rpms for that wattage. I might look into the 1up now.

FWIW, the numbers posted on that site for the Fluid2 pretty much correlate with what I see on my PowerTap when I'm riding.

^That chart seems awful optomistic. According to it, I can maintain 750W for 1min, and 400W for over an hour.

I've found that it correlates well in the 200-300W range with my PowerTap once the Fluid2 warms up (I've never checked for higher wattage... why bother when I have a PT?). That's with the recommended 2.5 turns on the tension knob.

Well then, if I don't go cat1 this year I'm holding you accountable for getting my hopes up ;)

just checked the PT file:
avg speed avg cadence avg power
20.72 102 211

I think something must be messed up then

Either the tire is slipping on the drum, or fluid has leaked from the resistence unit. In my experience the average power is about 100 watts low for that speed on a Fluid 2.

Of course as long as the PT is calibrated, just go off that and forget the speed.

I wonder if those black stains on my carpet might be fluid that leaked :rolleyes:

I suppose that explains my problem.

According to the chart here, http://curveship.dyndns.org/cgi-bin/aah/trainerpower.pl ...

Heh, since I put that page up, I'll point out my note on the "accuracy" section:



A note on accuracy: ... If you have a friend with a calibrated powermeter, ask if you can borrow it for an afternoon to determine your specific trainer's power equation.


Trust your Ergomo WAY over trainer calculations. (But also make sure your Ergomo is working right ... a lot of people have had to fiddle with their K value or redo the installation.) Also, specifically on the Fluid 2, see this post from cyclingforms http://www.cyclingforums.com/attachment.php?attachmentid=7758 showing power drift on the Fluid 2 as it warms up ... though there's a recent thread on the wattage board claiming that the newest units (last year or so) have helped with this.