Drivo Erg Mode

[Steve Rode]

Thank you, I received the email

[eraleous.constantinos]

I have the same problem, and I have to say that after spending and investing that money on this trainer I am very disappointed. It is very frustrating to see the power going up and down and varying 10-20 watts from our power meter!
How are we going to train and simulating trainings and races?

After all, that's the reason for buying a high tech trainer right?

[Elite Admin S]

I’m sorry for your disappointment.

Please notice that 10-20W variations are absolutely normal. As we said before, they are not due to the trainer but they depends on the normal differences between the pedal strokes. To demonstrate this, we have done a test with the brake blocked and we’ve registered the same variations.



We’ve also done some comparative test using other competitor’s trainers and measuring the power using an ergometer. All of them show the same behavior, as you can see in the links below:

Kickr: https://drive.google.com/open?id=0By4rZ ... GcxX3duMWc
Neo: https://drive.google.com/open?id=0By4rZ ... DVVcUtfY3M
Hammer: https://drive.google.com/open?id=0By4rZ ... DVVcUtfY3M

[dghcal]

Funny, I have the opposite problem. I can be riding along (ZWIFT) between intervals at say 200W before the trainer comes to a grinding halt - I switch to the lowest gear and the crank barely turns with all my force. ERG mode disengages itself, and after a few seconds I can slowly get the crank to turn again, eventually freely. ERG re-engages and we continue, now having failed the FTP test interval After a few minutes it locks again. I have stopped using ERG mode. Please advise, stopped using ZWIFT ERG mode

[djwalker1260]

To me this sounds like an underdamped servo system with too high of a gain- the trainer measures a power that is, for example, too high and then lowers the resistance. However, it lowers the resistance too much and now the power is too low. So it increases the resistance. Again by too much. And the power is too high again. Repeat this forever = sine wave appearance of power output. This could probably be fixed fairly easily by characterizing and re-tuning the servo loop. To me the erg mode servo feels quite "loose". I can pedal a fair bit above or below the target power and it takes quite a while to respond by changing the resistance. This is great in Zwift because you don't get unrealistically sharp changes in resistance. in erg mode you want it to be a bit more aggressive.

[jmess]

All of the Zwift training session I have done always have a watt target for the interval and the recovery. So if you slow your cadence and drop below the current Zwift Watt target enough Ergo mode will increase the resistance to the target watts at your new cadence within 3-4 seconds. So changing to a lower gear doesn't do anything for you. The problem seems to be once the resistance starts increasing for the new lower cadence, going from 90 RPMs to 70 for example, it ramps up too fast. If you react to the ramp up by slowing your cadence even more then you feel like you hit a wall because the resistance continues to increase/adjust to your cadence change. If you try and increase your cadence it can take 3+ seconds for the Drivo to start adjust to your increase in cadence. This delay/bug? can bog you down and if you are tired and/or less fit force you to stop pedaling until Ergo releases.

I run into this a lot when I try and get out of the saddle during a training session to stretch my legs or put out more power, my cadence tends to drop off 15-20 RPMs and resistance at my new lower cadence increases to match the watt target. When I sit back down and try and increase cadence I can get overwhelmed sometimes by the amount of time it takes before the resistance starts to adjust to my increasing cadence. As a mere mortal I sometimes have to stop pedaling and wait for Ergo mode to release. This whole sequence is unnatural and not something you experience in the real world.

Funny, I have the opposite problem. I can be riding along (ZWIFT) between intervals at say 200W before the trainer comes to a grinding halt - I switch to the lowest gear and the crank barely turns with all my force. ERG mode disengages itself, and after a few seconds I can slowly get the crank to turn again, eventually freely. ERG re-engages and we continue, now having failed the FTP test interval After a few minutes it locks again. I have stopped using ERG mode. Please advise, stopped using ZWIFT ERG mode

[jbroussia]

Hi,

I have the same problem with my Drivo: ERG mode is absolutely unusable ! I just tried to do a FTP test on Zwift, the resistance from the Drivo keeps fluctuating, and the fluctuations keep increasing with time ! At first it is almost unnoticeable but with time the fluctuations become bigger and bigger, until it is simply impossible to turn the pedals anymore. BTW I know how ERG mode is supposed to feel and work, I have another trainer interactive trainer which does it perfectly.

So my question is: I read somewhere (on these forums maybe ? can't remember) that Elite is going to release a software allowing to update the firmware of the Drivo. Should I wait for that software/firmware update, or should I return my Drivo for replacement ?

Thanks.

[wlsr9]

Hi,

When doing a 20 Min FTP test on TrainerRoad the app turns off erg mode just before the actual test commences. How do I control the resistance or slope of the DRIVO as in order to hit my target FTP power I am Having to considerably raise by about 10rpm.

[ahe]

Hello.

I have the same problem - using zwift. I used to have a Bkool trainer, and it worked fine. I could easily maintain my watt's stable during a ride. Both in training runs with fixed W, and just going around on the island or in London.

Now my watts are jumping up and down, even if i really try hard to maintain the same cadence/power it can go from 250 to 220 in a second. If i then stand up just for 2 seconds i go way above my 250 target.

Simply not what i expected from such a highly priced trainer. Hope someone out there have a soloution??

[Elite Admin S]

If you need a more stable power value in Zwift, simply raise the smooth option in advanced settings.
In the previous post is explained why you see more fluctuations with Drivo (high precision power sensor) compared to other trainers. As you can see in the comparison images, the other trainers simply doesn't show the fluctuation.

Regards