Anyone have a fluid 2 and power tap?

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If anyone has the Cycle-ops fluid 2 and a power tap I would like to know how various speeds on this trainer translate to power.

i have this setup and it works ok. although i dont know if this is correct, my educated guess is that the fluid2 is just a device to provide resistance. the powertap measures the amount of force generated at the hub. so i would figure that the powertap is accurate. although that is my opinion. i can say confidently the the percieved exertion is higher and the trainer does not allow any movement (like the road or rollers would). however, if it comes to riding outside when it is 20 degrees and a wind that is 25 mph vs. the indoor death machine, i would chose the death machine. lastly, to help fight boredom, get a TV or some form of entertainment. ask if you have any further questions. im here to help.

Because the fluid 2 also has a fan, the resistance is non-linear.

30 km/h=294 Watts
35.5 =350 watts
43 = 670 watts
25km/h=200 Watts

Here is my data from switching to speed in WKO display and reading peak speeds and related average watts.

YMMV...a lot.

I have a fluid2 and power tap. My experience is that the power/speed ratio changes constantly through out my rides. As the fluid2 continues to heat up it requires more and more power to generate the same speed. This does start to level off after about 30 minutes, but even then I'm not sure it ever does remain constant (although I hardly ever spend much more than an hour on the trainer so I don't have much data past that point).

Attached is a graph which shows this power/speed ratio change. The highlighted portion of the file was at a constant power of close to 260W. Yellow dashed line is the avg power over the hour (262W), blue dashed line is the avg speed (16.7mph). You can see that although the power remained constant the speed dropped from almost 19mph to about 16mph over the course of the hour with the majority of the drop off happening in the first 30 minutes.

I think this is going to make it hard for anyone to give you an accurate answer to your question (unless my experience is not the norm). Sorry.

I have a fluid2 and power tap. My experience is that the power/speed ratio changes constantly through out my rides. As the fluid2 continues to heat up it requires more and more power to generate the same speed. This does start to level off after about 30 minutes, but even then I'm not sure it ever does remain constant (although I hardly ever spend much more than an hour on the trainer so I don't have much data past that point).

Attached is a graph which shows this power/speed ratio change. The highlighted portion of the file was at a constant power of close to 260W. Yellow dashed line is the avg power over the hour (262W), blue dashed line is the avg speed (16.7mph). You can see that although the power remained constant the speed dropped from almost 19mph to about 16mph over the course of the hour with the majority of the drop off happening in the first 30 minutes.

I think this is going to make it hard for anyone to give you an accurate answer to your question (unless my experience is not the norm). Sorry.
Thank you for the reply.
I find this odd. Wouldn't the resistance decrease as the fluid heated up?
Carl at Kurt Kineitc told me that the fluid in their Road Machine maintains the same viscosity as it is heated up and as such their trainer does not see power/speed ratio changes.

I have a fluid2 and power tap. My experience is that the power/speed ratio changes constantly through out my rides. As the fluid2 continues to heat up it requires more and more power to generate the same speed. This does start to level off after about 30 minutes, but even then I'm not sure it ever does remain constant (although I hardly ever spend much more than an hour on the trainer so I don't have much data past that point).

Attached is a graph which shows this power/speed ratio change. The highlighted portion of the file was at a constant power of close to 260W. Yellow dashed line is the avg power over the hour (262W), blue dashed line is the avg speed (16.7mph). You can see that although the power remained constant the speed dropped from almost 19mph to about 16mph over the course of the hour with the majority of the drop off happening in the first 30 minutes.

I think this is going to make it hard for anyone to give you an accurate answer to your question (unless my experience is not the norm). Sorry.
I had similar experiences with the fluid2 - it took me about 30 minutes before the trainer stabalised - quite frustrating.

Thank you for the reply.
I find this odd. Wouldn't the resistance decrease as the fluid heated up?
Maybe the fluid expands as it heats up and that expansion causes increase resistance? Just a guess though. All I know about it is what I have experienced.

The data on this page may answer your original question... http://www.geocities.com/almost_fast/trainerpower/

I dug out a section of a training file in which you can see the watts increasing as the speed stays constant.


Over 5 minutes the watts increase from about 127 to 140.

I have a fluid2 and power tap.Here's a comparative file from a Kurt Kinetic Road Machine and Powertap Pro: 1hr @ 261w. Gridlines at avg speed and avg power for the interval. I'd say target speed increased from 20.7 to 20.9mph for a steady power.

http://i14.tinypic.com/34oa8ux.jpg

Here's a comparative file from a Kurt Kinetic Road Machine and Powertap Pro: 1hr @ 261w. Gridlines at avg speed and avg power for the interval. I'd say target speed increased from 20.7 to 20.9mph for a steady power.
Come on, couldn't you have found a file with 1hr @ 262W so we could have at least had an apples-to-apples comparison? ;)

Come on, couldn't you have found a file with 1hr @ 262W so we could have at least had an apples-to-apples comparison? ;)
LOL. I'll try for 262 tomorrow night. :)

After a 10 minute warmup, I've found my Fluid2 to be fairly stable. Just for kicks and giggles I first did a 10-minute warmup, then I did a 10-minute run at 285 watts wherein the average speed was 21.2 mph. After a 10-minute recovery, I did another 10-minute run at 285 watts with an average speed of 21.0 mph with no further speed degredation after that.

And, oh, BTW... As has been discussed on this board numerous times, 285 watts on the Cyclops has the same perceived exertion level (for me, at least) as 325 watts outside even with a towel, no shirt on, and a HUGE fan blowing on me. I'm sure if I used my trainer more often the two numbers would converge but the discrepancy only makes me less motivated to use the trainer.

--Steve

After a 10 minute warmup, I've found my Fluid2 to be fairly stable. Just for kicks and giggles I first did a 10-minute warmup, then I did a 10-minute run at 285 watts wherein the average speed was 21.2 mph. After a 10-minute recovery, I did another 10-minute run at 285 watts with an average speed of 21.0 mph with no further speed degredation after that.

And, oh, BTW... As has been discussed on this board numerous times, 285 watts on the Cyclops has the same perceived exertion level (for me, at least) as 325 watts outside even with a towel, no shirt on, and a HUGE fan blowing on me. I'm sure if I used my trainer more often the two numbers would converge but the discrepancy only makes me less motivated to use the trainer.

--Steve
The Fluid ^2 in my two 30 min seemed to settle out after about 14 minutes

It was a little disconserting at first but the non linear response in a trainer is more important than the exact speed at the warm up to power. Even after stabilized the any trainer can not be calibrated for every individuals frontal area. I am a big guy and push more air. Riders love to draft me. it is like riding behind a board. So compared to a smaller rider I would need to make more watts to go the same speed on the flats. So I am jus looking that it is close and the increase is similar.

As an aside I find it easiler to keep a higher steady power on a trainer than outdooors. Opposite of most people I guess.

If anyone has the Cycle-ops fluid 2 and a power tap I would like to know how various speeds on this trainer translate to power.
I have both, and they seem to corralate well. I do not enjoy using the trainer, but I just recently bought the Carmichael Training System videos, and they at least give me some better direction and sure help the hour + go by.