ERG Mode Flat, Uphill & Downhill


Last year I bought a Tacx Flux and was quite happy with that but in ERG mode it was acting strange when the road grade changed, easier going uphill and much harder going downhill, HR easily confirm that the power wasn’t the same.

So 6 months ago I upgraded to a Tacx Neo, not really because of ERG mode, just wanted a better trainer but I have the same problem now as I had last year, anyone else with this problem?

I try to pick a flat ride when doing ERG mode training but none is really totally flat and I feel that ruins the training a bit.

I do…
Have a Tacx Neo and have had a “discussion” with Zwift about it.
They said it was psycological and I was just imagen this feeling because it is what is what happens irl…

Well, the didn’t have any aswer then I said that I never ever experienced it easier going up and harder going down.

This is a issue I have had since day one with WO on my Neo, then when tired and didn’t want a DNF I used to head towards the mast :-/


Definitely feel the same effect (i.e. it’s somehow higher resistance going downhill in ERG mode) with my Elite Drivo. Not a really big issue for me though just a bit annoying when it’s very hard :slight_smile:

I have a Neo and I have never experienced a harder downhill than an uphill ride.  That being said, I have my trainer difficulty set to 50% because I noticed that I would spin out on downhill sections at 100% early on.  At my current setting I do feel the assist up to 5% decline but after that you have to push to keep your power up which makes downhills more like a flat but at higher speeds in SIM mode.  Frankly, I don’t even notice the climbs and descents as much anymore because it is all about the power you are putting out in Zwift.  As far as I know the only difference in trainer difficulty settings is how many gears you will have to cycle through on a given climb because power output is all  that matters, although cadence training is probably important for indoor riding too.  With respect to ERG mode during workouts, it ignores inclines and declines and as such asks you to output a certain power level regardless of elevation and tilt, so I guess I don’t understand what you folks are experiencing in that respect.  Maybe it is possible to use ERG mode outside of workouts but I have not seen how to do that.

Hey Haavard are you still experiencing ERG mode issues?

As Fez said, ERG mode is only for workouts and it is not affected by change in gradient. It should only affect you based on wattage and cadence. You can learn more about that here:–How-to-use-ERG-Mode-in-Workouts

Yes, still have the same problem in ERG mode during workouts but setting trainer difficulty to 0% helped a bit but I can still feel a change in power even when Zwift says it’s 200w and my HR easily confirms this.

Say I am doing a workout where I am to hold 200w for 20 minutes and on flat road after 10 minutes I have a HR of 165, I then start on a uphill, still 200w and same cadence but HR goes down to 155-160.

Opposite effect from flat road to downhill, Zwift says it’s 200w but my HR goes up and I can feel it’s harder to keep the same cadence. 

Difficulty setting have no effekt when doing workouts.
In ERG trainer sets resistance from the wo.
In non erg you have to change gears and cadence to generate the watt.

But still, with my Neo doing a wo say @ steady 200w with steady cadens, going up is easy er, going down harder.
Good place to test this in ocean boluard when going up to the marina. Litle easier going up and gets Litle harder when level out.

@Mikael Jonsson (Difficulty setting have no effekt when doing workouts.)

Uphill and downhill shouldn’t have any effect in in ERG mode during workout either but it does for some, even you and for me trainer difficulty either enhance or lessens that effect depending on if it is on 0% or 100%.

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