ERG vs Resistance accuracy

trainer

#1

I have an Elite Direto that supports erg mode. I love it for aerobic work but find that on VO2 intervals it fluctuates enough to put me “over the top.” I can carefully control my efforts and stay right on target in resistance, but in erg it floats around more and 10 seconds at 20 watts above my target is often enough to be the difference between completing a hard set and not. I just don’t even bother with erg on challenging workouts anymore.

My question is: do people find this to be the case on trainers that aren’t the Direto? Would a higher end smart trainer be any better at keeping the erg targets spot on or is it just the nature of the beast in erg?

And as a side note: my resistance efforts stay very close to the target TSS and IF, it’s not that I’m slacking on them.


#2

Over/undershooting targeted watts, slow to increase resistance to targeted watts are issues all smart trainers have in erg mode. Search around on the forum and I am sure you will find a user with same issue you are having. Seems to be most prevalent when the intervals are short (5-15ish seconds).


#3

So what you’re saying is I can’t tell my wife this is the reason I need to buy a Tacx Neo?


#4

Wellllll… haha


#5

Here is my ride with a Kickr 2017 last night. Some mild over/under shooting. But not bad. It depends heavily on how smooth and quick I adjust to the increase in resistance

First set:


#6

Here is my Kickr ride


Any thoughts as to why mine is so smooth? Every single ride is like this

Here is the link to the ride


#7

I had a lower end smart trainer (wheel on) and for doing hard on/off tabata type efforts it was useless. It was almost like the trainer couldn’t understand what I was doing!

Given that those efforts are really important to me I decided to swap my trainer for a dumb one, a Cycleops Jet Fluid Pro, (I also have a power meter) it handles those efforts great. For sweet spot training all it requires is extra focus to keep at the correct wattages. This works great for me, I’m not bothered about Zwift etc, just focused training so this simplified setup has been a huge improvement.

Not sure how well the high end trainers work but at the moment that investment would seem a waste of time for me.


#8

It appears that you have the “Enable Power Smoothing in ERG” option turned ON. That is the default from the factory.

Turn it OFF, and you will see it more like my ride.


  • Erg Mode Power Smoothing: this setting enables smoothing reported power to eliminate small inconsistencies in pedal strokes, making power graphs appear less erratic. Enabling is a personal preference, will not impact overall trainer functionality, and not required.

#9

ohhh. never really dug into the settings on the wahoo app. fair enough, thanks!


#10

I have a 2017 Wahoo Kickr and it is usable most of the time. To your point though, very short intervals of 15 seconds or less do get affected by the slight delay. In my experience with the Kickr, it actually ends up making the intervals EASIER rather than harder because it just takes 2-3 seconds for the erg mode to pick up and adjust the resistance to get my power up so by the time I’m 5 seconds in I’m still pretty rested.

I have found that playing around with cadence and the timing of your cadence increases for intervals can help it pick up quicker. Never felt the need revert back to resistance mode since I find it much more valuable to simply pedal and let the software do the rest.

Long story short, tell your wife you totally deserve/need the 2018 kickr to maximize your workouts :laughing:.


#11

I agree, tonight’s workout was Ebbetts and my kickr in erg mode simply does not adjust properly to these 5 second bursts during each interval. I found results were better if using a slower cadence but that’s against the workout text.
It’s super annoying, more than one burst literally only jumped 14 watts before dropping back down.


#12

Sometimes you just have to turn off the ERG mode.


#13

:cry:


#14

I just did Ebbetts this morning and it was no problem for me on Erg. I would see a bit of a power drop off immediately following the short 5 second spikes while the flywheel and erg caught up but it didn’t interfere with the workout at all.

Out of curiosity, are you using the Kickr’s power for the workout or using an on-bike power meter with power match?

Here is mine: https://www.trainerroad.com/career/mattymurda/rides/43666796-ebbetts


#15

Just using the kickr power so not power match involved.


#17

I have the same issue with my new bkool pro 2. For that reason I’m using often the resistance mode.