Direto XR problems with ERG mode

[jhankey]

Sjoyal, how long have you had yours?

[sjoyal]

I bought it two week-end ago. First WO academy #1 watts are going from 85 to 125 back to 70 with the same cadence. Try it again this morning, same problème. Did make the upgrade put of the box with Upgrado...

[enesto]

Hi,
I've sent a mail to support and their reply, that I can't agree, is the following. Translated via Google, no time to review the translation, but main points should be understood.
I still think we have a problem here, because an oscillation of 40 watts on a requested power of 150 and a steady cadence (+ or - 1rpm) is too much.
I'll ask deeper info, but for now this is the reply:
Good morning,

Thanks for contacting us.

Regarding your request:
The Direto XR is a high precision roller and the internal sensor measures 24 points for each pedal stroke
This means that it is able to measure with extreme accuracy both the pedaling non-uniformity or better the thrust between the right and left leg and the pedaling non-uniformity between one pedal stroke and the next.

This results in a power measurement of every single push on the pedals

Now it is not possible to have a 100% uniform pedaling (which is impossible even for professionals) the Direto XR measures every single variation of power that is produced

In ERG mode, therefore, this variance will continue to be seen and the roller will continuously adjust the resistance to obtain a value as constant as possible, but since the pedaling is not uniform, a constant power at 100% will never be possible.

This fact is not an effect of a roller problem but the direct consequence of its high accuracy

Here everything is explained in more detail: Power oscillations

If necessary, by increasing the Power Smoothing it will be possible to "dampen" this effect (which in any case will always be present even minimally)

I remain available
Yours sincerely
Andrea B.

[sjoyal]

This morning i did install the Elite My etraining app on my Windows pc. Connect everything with ant+ FC-E. Did a power training and send the .csv file to Elite support. Won't accept this explanation... Will return the unit to my LBS!!! Here is the result

test watt.jpg (45.34 KiB) Viewed 23629 times

[enesto]

Hi Sjoyal,
can I ask ho did you manage to upload images...
I cannot find a way... (I'm a forum dumb )

Thanks
Ernesto

[sjoyal]

Under reply, there is a tab attachments, from there chose your img file, when upload there is an option to place it inline

[jhankey]

Enesto, Sjoyal. I returned my unit yesterday and obtained a full refund. Elite are not listening here!! when you look at the graphs from dcrainmaker and gplama their power levels track the erg watts +/- a couple of watts. We are seeing 10s of watts variation above and below. As I try to regulate my watts to get it into the zone for the erg watts, as long as you are not overpowering the trainer in 52T-11 at 100rpm (LOL), it should settle within a couple of watts of the target easily, it simply doesn't do this.
I am pairing via bluetooth (PC windows 10)and on the pairing screen cadence ,power and controllable are all paired via bluetooth. My £230 tacx vortex does it better than this, that's an understatement as that actually works.
I was about to go and get another one today from a local bike shop but the recent posts from you guys have put me off. Elite are talking to people here who are really trying to get a good solution. If the smoothing needs setting at factor 50 to work properly this should be done at the factory. This will just be a small 'tuning' function anyway which just averages over more time... the problem here is that you end up with massive delays on terrain change on zwift and poor reaction times to go chase breaks from the pack, this kinda defeats the reason for paying £850 for a ' responsive ' trainer.

My spin down offset calibration number was the same as the label on the underside, so the calibration was perfect.

I really want this to work, the direto feels great when you are riding it and I believe its a really good bit of kit.

Enesto, not sure if you can upload a short video to them showing how bad the ERG mode tracking is,or maybe a quick whatsapp video with one of their engineers to see it. (BTW your English is better than mine!!)

Sjoyal, I cant think of any reason why it shouldn't pair properly using bluetooth on a pc, you may get issues if you were pairing to another device as well at the same time. FE-C again should also not be a problem... were you using a dongle for that?

Hopefully you will both get a solution, please keep posting on here and I will go and get another one if Elite can work out what is going wrong.
I may pop along to the bike shop and set one up there and buy it if it checks out ok. If I do I will let you know.

[sjoyal]

I’m still waiting for a reply on my support request. Last thing i want, is have to return It to my LBS. Has i’m a brand beliver, i bought everything from Elite, the mat, sweat protector, 2 towel and Sterzo smart. Don’t want to return all of this...

[enesto]

Jhankey thanks, my English can be improved a lot!!!

Trying to get an old version of camtasia to capture screen during a session.

I've added this image from MYET app to my ticket, average cadence 79.32 max 83 st.dev 1.13 ...I think it's quite stable.
That oscillation, in my opinon, cannot be explained by a not uniform pedal strokes...

Let's wait what's happening.

Cheers.

[jhankey]

ok, bit the bullet and managed to get hold of a second one from a LBS rather than on line. I explained the problem and he said, "no problem he will take it back if there is an issue," plus he is an Elite specialist dealer and has really good tech support here in the UK.
That's the good news, bad news is that it has the same issues. I have increased the smoothing to 10 also now but it still isnt good.

I am willing to give Elite the benfit of the doubt here. it may be measuring very quickly and there might possibly something like an aliasing effect going on with the reported power numbers, as I dont think I feel the 20-30w swings in power in my legs. ( Probably need to ride it more)

That said, the erg mode is not finding itself very quickly and Zwift keeps dropping out of ERG mode because of this.

As I have said, the trainer is super smooth. Gonna go ride on it for an hour or so to see how it behaves.
I really want this to work well, and it might be that Elite needs to average the power numbers that it sends to the apps a little more than they are doing to facilitate things like zwift ERG mode to work properly.