Fluid 2 Issue


(Justin Plasse) #1

I just bought a used Fluid 2 for use with Zwift. I made sure to select the Fluid 2 in the trainer list, but during my first ride, my readings and times are wildly inaccurate. Reading a constant 1200w and times that are half of what’s typical. I’ve never used a Fluid 2 before, so I have no idea how to judge the resistance, but I know it is not leaking. Also, I am using a Garmin speed/ cadence and ANT+. They seem to be working fine. Any ideas on troubleshooting this? Thanks!


(Crystal Haggard ZHQ) #2

Hi Justin! I checked your ride stats and it looks like the most recent ride you selected “trainer not listed” and the one before that you chose “Cycleops Jet Fluid”.  Next time you ride, pick “Cycleops Fluid 2”. It is the one at the very top of the list.  

If you are still having problems once you have the correct trainer selected, please open up a support ticket and we will help you troubleshoot further :slight_smile:


(James Prosperi SASCC) #3

Hi All

I have a Cycleops fluid 2. It is about 3 years old.

I have noticed that, as indicated by many others before, the wattage of the F2 output changes as the fluid warms up.

I recently did a test on the F2 using my calibrated Vector pedals and logged the data.

What I found is the following:

For the first 10 minutes of riding (ambient temp 17 C):

    - VP Zwift = 230 W average

    - Vectors = 150 W average

For the 20-30 min range:

    - VP Zwift = 227 W average

    - Vectors = 235 W average ( I increased my output due to climb)

For the 50-60 min range:

    - VP Zwift = 190 W average

    - Vectors = 192 W average

For the 65-72 min (ride end):

    - VP Zwift = 189 W average

    - Vectors = 186 W average

I have graphed these in Excel and fit a curve.

In the 200-300 W range there is an obvious change in % difference as the F2 warms up the fluid. This obviously takes some 30 minutes before it is really warmed up properly (in my garage anyhow).

In the early stages the Zpower watts on the F2 seem to be average around 80% higher.

By 20-30 minutes the Zpower actually dropped about 8% below the Vectors average power output readings.

As I approached the 50 minutes or so the power began to become consistent between the two.

I have not tried but might look into getting a small heater to warm the fluid up prior to starting ride and see how this works. If this works then it would be an obvious way to start closer to reality. Other option is to warm up your legs for 30 minutes before racing.

If people are racing and rider A is using Zpower, then they will have a considerable advantage over a power meter if all else is equal. Rider B may be creating 80% less power for the first 20 minutes or so.

I guess power is power, so when using a power meter all should be fairly equal, as long as there is no doping, and the power meters are all calibrated properly.

Zpower is the issue, and by the looks, it only results from the Fluid trainer power curve being based on the fluid at a particular operating temperature i.e. a certain minimum viscosity.

It would be nice to see a solution to this, like an adjustment that could phase in over the first 20 minutes. Otherwise its either Power meter or a small heater!!

Interested in others findings and observations.

Ride on!

James


(Michael Lawrence) #4

Cross posted more here

https://support.zwift.com/hc/en-us/community/posts/204112753-zpower-too-high-why-