For years I have been using Tacx Vortex smart trainer. I typically use the Trainer Road Tacx Cycling apps. Last month I purchased a Tacx Flux S smart trainer. I have not used the Flux much due to focusing on running but the few workouts I have done on the Flux are much much more challenging. The Trainer Road and Tacx Cycling settings have not changed. I realize that speed does not mean much, but my trainer speeds have dropped from about 19/20 mph on the Vortex to 14/15 mph on the Flux. December is the first workout on the Flux, the previous on the Vortex:
Are you riding your workouts on the same gear between both trainers? And, are you using ERG mode?
In ERG mode, the speed is solely driven by the gear you choose. For the same workout on the same trainer, you could ride the same effort but go 12 MPH or 35 MPH just by selecting a different gear and changing nothing else. Same effort.
Same bike, same gears, similar courses (typically flat to slightly rolling), same settings, calibrated prior to each workout. Different trainer: Vortex is a wheel on trainer and the Flux is a wheel off trainer.
Same bike, same gears, similar courses (typically flat to slightly rolling), same settings, calibrated prior to each workout. Different trainer: Vortex is a wheel on trainer and the Flux is a wheel off trainer.
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P1/T1 = P2/T2
If you start with a certain tire pressure P1 at the start of your workout at a given temp in Kelvin (T1), by end of workout your tire with the same volume has a new temperature of T2. This means the pressure on the wheel on contact point P2 = P1 *T2/T1. It is not "nothing. If tire temp was 20C or 293 Kelvin at start, and end up at 30C or 303 Kelvin at the end, now your new pressure is 303/293 of your original pressure on the wheel on part.
Your direct drive trainer removes all that.
Keep in mind that your calibration rolldown test iteself my be flawed and give you too high a score to start with which implicitly gives you too much “wattage credit” starting the ride and even though the pressure goes up by end of ride bringing the actual wattage closer to reality, it may not be enough to offset the too high roll down calibration “credit” factor.
Hope you figure it out. I went from a Cycleops Fluid 2 to the same Tacx Flux S trainer as you. I like the Fluid 2 trainer and find that I can’t seem to figure out the new Tacx. I have it in ERG mode and it will sometimes get randomly really hard or I have to spin at 110 rpms to hit my power number. I don’t get it.
I am probably doing something wrong, but not sure what…
I have a Tacx Vortex and it drastically overestimates power, especially when the rear wheel is spinning fast, which is how I prefer to ride it so the tire slips less. I have a Quarq power meter, so I can see the Quarq readings at the same time as the Tacx Vortex readings, and when I’m spinning fast the Tacx reads about 40 watts higher than the Quarq. So, likely your new trainer is just a lot more accurate than the Vortex.
I will try the above recommendations this evening. I struggle to get up to the 30kph required to calibrate the trainer. Perhaps it is the heavier flywheel on the Flux compared to the non flywheel of the Vortex.
I will try the above recommendations this evening. I struggle to get up to the 30kph required to calibrate the trainer. Perhaps it is the heavier flywheel on the Flux compared to the non flywheel of the Vortex.
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I have the Flux S and can hit the calibration speed easily when I’m on the big ring on the front.
But (using an ipad for the controller) I find that I have to unplug the trainer before starting or (either the ipad or trainer) won’t do erg control (where I don’t have to shift). I can’t figure out which is to blame but garmin was no help when I asked for help.
I switch between a P2 and R3 with a 10 and 11 speed cassette so I like to just stick the rear gear in the middle and erg it out.
Hope you figure it out. I went from a Cycleops Fluid 2 to the same Tacx Flux S trainer as you. I like the Fluid 2 trainer and find that I can’t seem to figure out the new Tacx. I have it in ERG mode and it will sometimes get randomly really hard or I have to spin at 110 rpms to hit my power number. I don’t get it.
I am probably doing something wrong, but not sure what…
I feel like it’s time for my public service announcement. Flux S user here, didn’t want to get an ANT+ dongle, because I felt like a $750 trainer shouldn’t need another 50 dollar part. Well, after 2 months of pissing and moaning bought the 15 dollar Amazon version with a USB extension cord and boom! Zwift bliss.
Theoretically it’s just that the radio wave that Bluetooth uses is just too crowded. Remotes, baby monitors, yada yada. All I know is the dongle fixed my fallout mystery resistance problems.
Hope you figure it out. I went from a Cycleops Fluid 2 to the same Tacx Flux S trainer as you. I like the Fluid 2 trainer and find that I can’t seem to figure out the new Tacx. I have it in ERG mode and it will sometimes get randomly really hard or I have to spin at 110 rpms to hit my power number. I don’t get it.
I am probably doing something wrong, but not sure what…
I feel like it’s time for my public service announcement. Flux S user here, didn’t want to get an ANT+ dongle, because I felt like a $750 trainer shouldn’t need another 50 dollar part. Well, after 2 months of pissing and moaning bought the 15 dollar Amazon version with a USB extension cord and boom! Zwift bliss.
Theoretically it’s just that the radio wave that Bluetooth uses is just too crowded. Remotes, baby monitors, yada yada. All I know is the dongle fixed my fallout mystery resistance problems.
I bought a 4iiii heart strap that supposed to work with Ant and iOS and it didn’t work for me. I then bought a Cable device (not a cable) almost worked but I still need to unplug the Flux between rides, I find that starting the garmin trainer app and confirming that i can increase resistance before starting my Rouvy workout works best.
It would be nice to have Ant+ support on an iPad but I’m not finding that. I never knew how well Ant worked until I got a bunch of bluetooth devices and have to fight them. For example going from my rower to my skierg I have to connect/disconnect the heartrate strap, etc.
I feel like it’s time for my public service announcement. Flux S user here, didn’t want to get an ANT+ dongle, because I felt like a $750 trainer shouldn’t need another 50 dollar part. Well, after 2 months of pissing and moaning bought the 15 dollar Amazon version with a USB extension cord and boom! Zwift bliss.
Theoretically it’s just that the radio wave that Bluetooth uses is just too crowded. Remotes, baby monitors, yada yada. All I know is the dongle fixed my fallout mystery resistance problems.
BLE and ANT+ both use the unlicensed 2.4GHz spectrum range, but the ability to shove the ANT+ dongle next to the trainer often wins through brute force. If anything, BLE should be more robust due to more error detection/correction capabilities - I believe this is reason BLE is preferred in HRV analysis applications.
Edit: if you buy an ANT+ dongle make sure you also buy an USB extension cable so you have control over the placement of the dongle, otherwise, you may have the same (or worse) interference issues as you’re having with BLE.
I feel like it’s time for my public service announcement. Flux S user here, didn’t want to get an ANT+ dongle, because I felt like a $750 trainer shouldn’t need another 50 dollar part. Well, after 2 months of pissing and moaning bought the 15 dollar Amazon version with a USB extension cord and boom! Zwift bliss.
Theoretically it’s just that the radio wave that Bluetooth uses is just too crowded. Remotes, baby monitors, yada yada. All I know is the dongle fixed my fallout mystery resistance problems.
BLE and ANT+ both use the unlicensed 2.4GHz spectrum range, but the ability to shove the ANT+ dongle next to the trainer often wins through brute force. If anything, BLE should be more robust due to more error detection/correction capabilities - I believe this is reason BLE is preferred in HRV analysis applications.
Edit: if you buy an ANT+ dongle make sure you also buy an USB extension cable so you have control over the placement of the dongle, otherwise, you may have the same (or worse) interference issues as you’re having with BLE.
All this said, I had an experience where my set up that used to have these issues - then I got everything to work all dandy for several months - once again started having similar issues. They were solved by buying a newer USB extension cable. I have no idea how the prior cable became bad, but when all else fails: try a new cable.
