Tacx Neo 2 Smart spin-down failing

Has anyone else had issues getting the first spindown calibration on a Neo 2 to complete?

I’ve tried it ~10 times, including disconnecting my watch and headphones from Bluetooth, and set my phone on the floor next to the trainer. Trainer is connected to AC power supply; TrainerRoad app on iOS.

I’ve ridden it twice now, and it routinely reports 10% lower power readings than my Stages I have been using. This is what makes me think I need to get the calibration to complete, 10% difference is too much, I think.

I’m not useing Tacx Neo 2 myself, but I was under the impression that Neo/Neo 2 wouldn’t need a spindown at all.

I read the same thing, but I also read in tacx support that it needs one initial spin down.

This Smart trainer is the only trainer that doesn’t require a calibration process


“With direct-drive trainers the calibration process takes seconds. It ranges from a simple spin down procedure, to not necessary at all in the case of our NEO trainers.”

Correct, do NOT attempt to calibrate the Neo trainer.

That last quote is confusing, because it says “it ranges from a simple spin down procedure to not necessary at all.”

And that article then gives instructions on how to do the spindown using their app. Doesn’t make sense to give instructions on something that isn’t necessary.

If it isn’t a calibration issue, has anyone else heard of Stages meters reading significantly higher than another power source?

I’ve used 3 Stages power meters on 4 bikes for the last 5 years, all with consistent power data and fitness trends. Do they just give out higher numbers?

Variation between different power meters and trainers is very common, unfortunately.

If you have a power meter for use outside, it’s best to use the PowerMatch feature in TR that uses the meter for setting resistance.

I didn’t want to immediately disregard the power data on a brand-new high-end trainer.

Without power match, though, my outdoor rides’ TSS will not jive with my indoor.

Powermatch it is, I guess.

I have a NEO 2. No calibration is necessary.

It’s probably one of two things, or more likely a combination of both.

If it’s a left only stages then it’s likely to be caused by a slight left right imbalance. That and as the drivetrain causes losses in power due to friction measurements at the hub tend to be lower than measurements at the crank.

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Understandable, but this picture of multiple power devices is not as clean as we would all like.

Consider the initial fact that the Stages is actually only measuring power on one side and doubling the value. The Neo is actually measuring both legs. Any imbalance you may have will impact the variation seen between both devices.

Also, the Neo is shown to lose accuracy a bit in higher gearing. It is quite solid in the small ring.of a road bike. But will go a bit off at higher flywheel speed common with big ring and small cogs.

Those 2 issues may well address the differences you are seeing (not sure as there is no data to review). And there are more possible causes to the differential, so it’s more likely that your devices won’t match than that they will.

It all gets to the problem that Shane Miller has mentioned more frequently as of late, where the power measurement industry has some things to get straight.

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This all makes sense, I just don’t like it haha.

I was hoping to eliminate the Stages from my trainer bike, 1 less battery to keep track of, etc.

If the trainer and outdoor meter were 1-2% apart I could live with it, but the 10% difference changes training zones in workouts.

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Sadly, your experience is pretty common. I’ve read numerous cases just like yours. Many of them on the Neo FB group, where the Neo and their meter don’t match, and it sometimes exceeds the tolerance range of both devices (meaning one or both are possibly out of spec).

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I use my Neo as a baseline for all my other powermeters here’s how they differ:

4iiii - 9,5%
Stages XTR - 7,5%
Assioma Duo - 1,6%

My legs usually have a 48%L/52%R distribution, that + oval chainrings would probably account for most of the difference.

The worst part of Stages is their inability to add scaling that 4iiii has.

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The quote is not remotely confusing to me.

In your quote you omitted the end of the sentence that explicitly states that calibration is “not necessary at all in the case of our NEO trainers”.

The instructions to calibrate using the app are clearly for the other, non-Neo Tacx trainers, that do require calibration.

How much clearer could Tacx be?

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It’d be clearer if the “in the case of the Neo” part was a separate sentence altogether. At a minimum, I think the sentence is lacking a comma or parentheses.

We’re splitting hairs at this point, Neo needs no calibration. Point taken.

Can you calibrate it if you wanted to or it does not have a calibration feature at all?

No, it is not possible for the user to calibrate the Neo.

That is only done in the factory.