dtm said:
Hi I have recently bought a Tacx flow for my Winter training. I have adjusted up the roller pressure to the minimum before any tyre slip. I am running 8 bar in my tyres (115-120 psi) My calibration result comes up at between +8 and +10. I was wondering what calibration results do other users get ?
Is it normal to get this high number and will it affect the accuracy of my training. If I release the roller/ tyre pressure to the point that I get a reading of 0 - +3 or 4, I get tyre slip all the time. I have tried different tyre types as well
I am also pretty sure the trainer is set up correctly
Thanks
Dan
If you run the calibration test right at the begining, you'll get such a high value (> +4).
But run it 20min into your workout, and it's already lower. Run it again 30min into your workout and it's even lower.
The prescribed 3min warm up before attempting a calibration test isn't sufficient imo.
So put as much pressure as you can in the tires. Then process a pre-calibration if you want. But the real calibration prior the real effort, you should do it at least 15-20min after the begining (basically this period becomes your warmup).
If you don't do it, if you leave the calibration result to +8, you'll loose a lot of accuracy as a result of this power drift occuring as you put more miles.
Also be aware that the Flow isn't known as being accurate. Far from it. It's not even constant. It will overestimate the power at "higher cadence/lower power", and may be fairly accurate at "lower cadence/higher power". In other words, my Flow over estimates power by as much as 50w at 240w/100rpm, and may be spot on at 320w 70rpm.
It seems that Tacx has solved this issue with the release of their iMagic, because this model uses cadence values as a dynamic variable in their power extrapolation algorythm. This unit (the iMagic) will not even allow you to ride over 40w if the cadence sensor isn't installed and working.
