Watts seem really low

(Tony Otero) #41

Guys,  I gave up on the Fluid 2.  Could never get this working properly.  I even took the flywheel off,  which helped a bit but without inertial momentum it was literally a drag.I decided not to drill out some of the fluid (my other great idea)  and risk ruining the Cycleops.  What I did was I gifted it to my son who just uses it for spinning.  I then bought the Tacx Blue Matic Mag trainer at US $150 (Amazon) it is a great buy.  At recommended resistance 3 level it is easier on the knees and the power curve is linear so it doesn’t get increasingly difficult increasingly fast. I will let the young riders deal with the progressive fluid resistance. Too hard for me given the so-called calibration with Z power in Zwift.  Anyway,  I really can’t recommend the Blue Matic  enough. It is about as stable and well  built as the Fluid 2.  If you are a strong rider they have a higher resistance curve model too.  Of course they also have Smart Trainers.  But just speaking for the Blue Matic,  I have  ridden with other riders, drafted,  as well as helped  pull some charity rides that I came upon. Best is that as a “B”  rider my average speed are similar to my outdoor rides (although my indoor downhills seem to be faster)  definetly more fun and probably my least cost way to solve the Zwift issue. 


(Tony Otero) #42

Jeremy,  your test makes all the  sense in the world to me…has to be as much as 40% off. The increase over time is something I hadn’t thought about but I can see that too especially with how my speeds would go down on longer rides.   I did an FTP test and tried mightily hard to ride at decent pace and the long test almost ruined my knees. 


(C) #43

Hmmm… suddenly (is it just my imagination?!) my Fluid2 sounds loud and broken. Maybe it is time to replace it!   : )



(g gerasimos) #44

@Zwift — can you simply load up a more accurate power curve for Fluid 2 trainers? Or does any body know another trainer that can be selected that will get closer to the actual power curve of the Fluid 2?  Frustrating to ride “slow” but worst is that I can’t ride with folks I know because they’ll drop me in a minute given the low power numbers. 


(C) #45

This became a really long conversation thread, which I participated in a few times. Just to bring it to a bit of a conclusion, at least for myself, and corroborate what a few other people mentioned… the “old” Fluid2 definitely doesn’t work properly with Zwift.

I bought, and rode for the first time today, a Tacx Satori Smart, and there was definitely a big difference. I’m not as good with data as some of the other commentators here, but I observed at least this much:

“old” Fluid2 = for something like an hour and a half ride, I could handle somewhere between 1.7 to 2.2 watts/kg through the ride.

Satori Smart = for the same kind of ride I could pretty easily handle 2.5 to 3 watts/kg  through the ride.

For the biggest climb in the island course… I used to push myself hard and be able to manage maybe 2.7 up that hill. Pushing myself on the Satori Smart on that same climb I was doing around 3.7.

So, I don’t know. Case closed for me. I gave up on the “old” Fluid2.



(Chris Jeffree) #46

Damn it. I just started using zwift with a second hand Fluid2 (grey 2008 model http://www.amazon.co.uk/CycleOps-Classic-Fluid-Trainer-Incl/dp/B000BT7HWY) which I just purchased and could only manage 120W on a FTP test this morning. Most of my rides on strava estimate it at 160W. Seems to be a similar error percentage as you guys are reporting.

I only went for the Fluid2 because it was in the supported zpower list, had no idea there were different versions. Really wish we could get an accurate power curve for this older model as it seems quite a few people are having similar issues.

Guess I’ll try the tacx blue motion power curve and see how that feels…


(Tony Otero) #47

Chris, I tried the different curves, worked with Zwift support, removed flywheel, etc and finally gave up on my Fluid2 and bought a Tacx Blue Matic ($175). It is a magnetic trainer and at level three it works well with the standard calibrated Zwift power curve. There’s also the ability to push up or down the resistance as needed. While spinning, the increase in resistance is linear and not nearly as aggressively hard as the Fluid2. If you really really spin it up it can run out a bit but under normal cycling conditions this is not a problem. This one does up to 700 watts and I believe there are 950 and 1500 watt models that are a bit pricier (if you are an elite rider). They also have smart trainers with variable resistance (more money). The Blue Matic is as stable as the Fluid2. Good quality. Very happy I bought this. Gave away the Fluid2 for non Zwift use.


(Eric ) #48

Strava Estimate of FTP != actual FTP. My Strava Estimate is 250watts. If I held that for an hour I think I would die.


(Alex Oliveira) #49

Fluid 2 definitely doesn’t work with Zwift. Unfortunately. I’m not the worst cyclist in the world as zpower is showing me every single day! :frowning:


(Eric ) #50

@Alex - The Fluid2 most definitely works with Zwift. As with all estimated power, there will be some fluctuations but it tends to *over-report* rather than under-report power.

I would look at your set-up first and make sure that:

  • tire pressure is set to 100psi
  • tire size is 700c
  • the speed-sensor magnet is properly placed
  • the speed-sensor battery is fresh
  • and that the ANT+ dongle (if you are using one) is within a foot of the sensor itself

It’s the most tested zPower trainer next to the Kurt Kinetic Road Machine.


(Chris Jeffree) #51

@ Eric C. - What about different versions of the Fluid2, ie. 2008 model vs 2013 model?


(Alex Oliveira) #52

@Eric C. - Fluid2 after 15~20min increases resistance (Using the same cadence, same gear). I think it happens when Fluid2 becomes hot.


(Eric ) #53

No difference unless the 2008 one starts to leak (as they were more prone to do back then). We do compensate for the fluid heating up as well (our office has a cool infrared-thermometer just for this).


(G Nguyen) #54

I have a cycleops fluid 2 also (2004 model) and also a power tap yellow hub and shark fin wired sensor (does not communicate via ANT).  I’m using zPower with a garmin speed/cadence sensor.  On screen watts read 30W too low, power tap says I’m doing 180-190, just at threshold. zPower shows 150W and I can’t keep up with anyone. I’m 165cm / 67kg.


(Super Syes) #55

Just wanted to chime in and report I’m having the same issue with my Cycleops Fluid2 trainer. My watts seem very low. It’s an older model (gray with the yellow knob). Any assistance would be appreciated.


(G Nguyen) #56

I just ordered a powertap dt swiss r460 wheel. At $570 it’s the cheapest option, it will broadcast ANT+ power data so I can use with any trainer or rollers.


(G Nguyen) #57

My old wired powertap shows 200w for 2x20s so with accurate power numbers and drafting I might have a chance of staying in the zwift field.


(g gerasimos) #58

Come on Zwift. Do the math and update the curve.


(G Nguyen) #59

They would have to add another curve for the old Fluid2 trainer.  They don’t seem to be in a hurry to do this as there are not enough people with this trainer to make it a huge priority for them.  I prefer the rollers anyway.  There seems to be a lot of vibration coming from the tire contact point (Gatorskin tires).  Rollers are a lot smoother but require a ANT+ power meter.  I will be on Zwift again once my new powertap comes in.


(Super Syes) #60

@ Maurizio Gigliotti I tried the Tacx Blue Motion trainer and while it seemed to improve things, especially at the low-end, it is still inaccurate, particularly at higher wattage thresholds.

I agree they need to add another power curve for the older fluid 2 trainer (just label it “Fluid 2 Legacy Gray Model” or something similar). The newer/current gen model could remain as-is.