Speed Fluctuations

Does anybody else have speed fluctuations particularly when using the NPE Runn?

Say I set the treadmill you 8mph, the speed zwift reports bounces between 7.8 - 8.2 continually. I know factors such as me stepping on the belt slows it and also motors are of varying quality in terms of counteracting this.

Would be great if Zwift could do a 3 second average of pace so it doesn’t continually adjust the reported speed on the screen. Over the run the reported pace is very close to what the treadmill is set to, maybe 2 seconds per mile difference but seeing the reported pace constantly changing is quite distracting.

Am I alone in this?

Same for me although the variation is not as great as 0.4mph. I have found with my treadmill (acknowledging all are different) that a warm-up brisk walk under 5.0mph is dead on. Easy jog at 6.0mph is same for Zwift and treadmill with very very little variation. As I get to 7.0mph and higher the numbers bouncing up and down are meaningful. Most likely the pounding on the treadmill. I made a box to hold the NPE so it is no longer attached to the treadmill and that eliminated a lot of variation from bouncing the treadmill platform. For my experience, the difference doesn’t seem to be more than 0.1-0.2 which is acceptable in my opinion.

As you mentioned, the average over a mile is always about the same as the treadmill but the running curve when done has a number of spikes when you review after a run. The NPE product is a good one and I’m still thrilled with it. I do like the idea of a 3 second smoothing option.

Thanks for the reply, it seems you experience the same as me. I’m going to experiment with different stickers on the other side of the belt and mount the cradle on velcro so I can move it around a bit to see if anything changes. If you’ve mounted yours off the treadmill so to speak does it still pick up the cadence accurately?

I have noticed the same issue at lower speed even after I’ve calibrated the sensor, the graph along the bottom is a saw tooth pattern, when I increase the speed above 10.5km the graph smooths out with very little fluctuations

Since it’s off the treadmill it doesn’t pick up the cadence well. I had a Zwift Run Pod prior to the RUNN so I use it (when I can find the sucker, I misplaced it a couple weeks ago).

I find the same thing, and variation with speed in about the same ranges.
Cadence is really averaged it seems - over quite a long time span.
I would like an averaging like described too for speed. (In swift mind you)

I have also found, that as soon as I calibrate the Runn - it immediately stops sending any data to Zwift. Even if I only calibrate inclination (which is way off in my case) - all data stops. I have to revert the Runn back to factory default for it to work.

I have reported this to NPE, and they are looking into it. Hopefully a future release will resolve this.

Ok, so I guess the issue is quite common then. I have a commercial treadmill at work which I have linked to Zwift but I’ve not really tried it properly. I’ll test in on that and see if it’s more to do with the quality of treadmill.

I’ve no issue with the cadence but to be honest I’ve nothing to compare it to. We all run different so there’s no point me saying it’s different to my mate for example. It doesn’t however bounce about.

Reference the lack of response after a calibration. I’ve not had this issue at home Patriq but the work one I’ve had to do a reset on a couple of occasions to get it back into life. It’s done this without running a calibration too where it just doesn’t respond until a reset.

NPE seem quite good at looking at these issues so hopefully updated firmware is around the corner.

Been in touch with NPE. They say not to use the calibration tool in Zwift and to calibrate it using Configurez. By design the Runn is accepted to fluctuate up to 0.3mph of the calibrated speed.

There is no power smoothing option albeit this is something zwift could do.

I’m going to give it a go with the configurez calibration. It does say to calibrate off the treadmill but that’s a health and safety warning and ideally it needs calibrating whilst running for greater accuracy. I’ll report the results.