I recently got a Kickr Bike Shift. Other than a poor service delivering it by Wahoo, I’m happy with the purchase so far.
I’ve noticed that ERG mode in all the apps I ride on (SYSTM, indieVelo, and Zwift) doesn’t seem to be as hard capped as it is riding on a standard Kickr trainer. It’s extremely easy to break out of it. Riding on my Trek hooked up to my Kickr in ERG mode, the green bar in SYSTM that writes your power as you ride would be essentially perfectly straight and the power would hold at the target (MAYE a watt below). On the Kickr Bike Shift, the power is much more volatile, fluctuating quite regularly, though probably averaging out around the power target for the given segment.
Could be that you had erg mode power smoothing on for the Kickr (where it reports the fake perfectly flat power rather than what you’re actually doing, on by default, boo) and don’t for the Shift (so are actually seeing what you’re doing, yey). It’s set/unset via the Wahoo App, not SYSTM, so you could check that there.
I was taken aback by this when I first got my Shift as well. The first thing I checked was that power-smoothing was on - it was. I did a bit of research and it seems that this is to do with the difference between the drive system in the Shift compared to the Kickr turbo trainers. Like you say, over the course of a given interval it works out ok. I think the long term effect for me will be to smooth out my pedalling action.
Yeah, same for me. I can definitely sense a pull toward smoothening out my pedal stroke already.
I just liked the hard cap feeing with the Kickr trainer cause I work a decent bit on the bike and not having to focus as much about exceeding the target was pretty convenient.