Hello Everyone,
I wanted to turn to the knowledge of the community to see if anyone can help me understand something I saw in today’s workout.
I did Carpathian + 2 this morning and really struggled through it, so on the last interval of over and under I resorted to doing several 3 minutes out the saddle pedalling.
I was on a smart trainer (Tax Neo) and using ERG mode so I thought the power would closely follow the target but when I was riding and, more evidently, when I analyzed the workout I saw that actually the power I was producing was way under the target:
Why is this the case given I was in ERG mode? Shouldn’t have the trainer just adjusted the resistance? Did this level mean my trainer didn’t have the capacity to produce that resistance (seems unlikely)? Is this a measurement error (felt hard, but also seems unlikely)?
Trainers seem to react slower at slower cadence, I can’t really explain why but mine does too (though not this far off). Did you feel any flywheel slippage while doing these intervals? The Neo I tried was awful with this and I’m sure it would impact readings
What gearing were you using for the seat and then standing efforts?
How “smooth” are you at standing like this? Do you have the “chain gap issue” where you get the slack and tap of the freewheel, or are you keeping good tension on the chain around the circle?
Given I was riding in ERG mode the gearing didn’t change throughout the workout and I’m pretty smooth when standing so I never notices any loss in tension. I will check this on my next ride, I haven’t changed the chain in a while to be honest.
I would shift when you stand and sit. That would keep the trainer flywheel speed more consistent and require less adjustments from the trainer when in erg mode. If you don’t shift you are going to see big swings in flywheel speed / power as you change positions and some lag with the trainer adjusting resistance. I have seen as well as you are now that perception of power / RPE when changing positions between sitting and standing does not always match reality. The power looks on target during the interval when you move back to sitting.
It takes a little while for the trainer to recognize a power drop and adjust cadence, and on the sawtooth intervals like that it will always be chasing the target power. I suspect if it was flat power over/unders the power would have more closely matched the target. But it does look a little laggy in responding.
Thanks a lot @mcneese.chad, very useful and I’ll read the article!
@Gnome, I think you might have hit the nail’s head. I was indeed running TrainerRoad through Bluetooth and Zwift through Ant+ (not controlling though). Was this the way you were running it when you experienced the weird behavior?
One possibility is that the low cadence efforts on that gearing put the Neo into a situation where it can’t generate the necessary resistance at the “flywheel”, and it feels like slippage.
A couple of ways to test this:
Ride at 150 watts at the same low cadence
Ride at 300 watts at the same low cadence in a bigger/harder gear Eg big ring, lower half of the cassette.
If the Neo behaves normally in these situations, that points to some form of slippage. And if this is the case, seems like a defect in the trainer - as the power/cadence/gearing you’re riding at don’t look that extreme.
I’d be a little surprised if it’s the BLE/ANT thing, as the trainer was working fine when pedaling under “normal” cadence. But worth checking to confirm.
Elite Direto (ERG with low gearing) and I usually see a significant dip in power when initially when I get out of the saddle. It can take up to 10-20 seconds for ERG to bring the resistance back up to target. This is counterbalanced by a spike in power when i return to the saddle and increase cadence.
I think the point is, the Neo isn’t really limited. I could be wrong, but my understanding is it’s high and low ends do not require any shifting avoid ceilings or floors in a normal cassette range. I ride in the same gearing from my easiest recovery in the 70’s to whereever I top out on, nearly 1000.
