Stages Gen 3 vs Tacx Neo waaaay off

A light bike doesn't replace good fitness.

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AJS914
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by AJS914

Do you have access to another bike with power that you could put on the Tacx Neo for comparison?

by Weenie


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nickf
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by nickf

No other power meter yet. But will be picking up another one for my gravel bike once they are back in stock from Stages. Then I will be able to compare the two.

I did speak with a cycling coach today and gave him some of my ride data. I do ride with him regularly. With the numbers I gave him and what he knows about me he is confident that for whatever reason that Tacx is off. The stages numbers are more in line with what he knows about me and how I ride. Also like others said FTP # isn't the end all be all, as long as the data is consistent. I have a lot to learn. I will still try to track down another smart trainer to give it a go and see how it compares.

glepore
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by glepore

nickf wrote:
Fri Jan 10, 2020 11:34 pm
No other power meter yet. But will be picking up another one for my gravel bike once they are back in stock from Stages. Then I will be able to compare the two.

I did speak with a cycling coach today and gave him some of my ride data. I do ride with him regularly. With the numbers I gave him and what he knows about me he is confident that for whatever reason that Tacx is off. The stages numbers are more in line with what he knows about me and how I ride. Also like others said FTP # isn't the end all be all, as long as the data is consistent. I have a lot to learn. I will still try to track down another smart trainer to give it a go and see how it compares.
In my experience (I've had 6 or so stages of all gens thru here, along with quarq's, p2ms and srms) stages are pretty solid given the inherent limitations of 1sided power.

Just a note before you get a stages for a gravel bike, though, check for chainstay clearance first. Many gravel bikes have chainstay clearance issues with the pod when using cranks with "road" length spindles...including some that don't take crazy wide tires.
Cysco Ti custom Campy SR mechanical (6.9);Berk custom (5.6); Serotta Ottrott(6.8) ; Anvil Custom steel Etap;1996 Colnago Technos Record

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nickf
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by nickf

glepore wrote:
Sat Jan 11, 2020 12:21 am
nickf wrote:
Fri Jan 10, 2020 11:34 pm
No other power meter yet. But will be picking up another one for my gravel bike once they are back in stock from Stages. Then I will be able to compare the two.

I did speak with a cycling coach today and gave him some of my ride data. I do ride with him regularly. With the numbers I gave him and what he knows about me he is confident that for whatever reason that Tacx is off. The stages numbers are more in line with what he knows about me and how I ride. Also like others said FTP # isn't the end all be all, as long as the data is consistent. I have a lot to learn. I will still try to track down another smart trainer to give it a go and see how it compares.
In my experience (I've had 6 or so stages of all gens thru here, along with quarq's, p2ms and srms) stages are pretty solid given the inherent limitations of 1sided power.

Just a note before you get a stages for a gravel bike, though, check for chainstay clearance first. Many gravel bikes have chainstay clearance issues with the pod when using cranks with "road" length spindles...including some that don't take crazy wide tires.
Yeah I think the stages is a no go on the checkpoint. Near the battery door of the stages housing it's 10mm but closer to the bb it's thins down even more. Using a sram red crank. I'm almost convinced it would technically fit but would leave no room for flex or a grain of sand.

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ms6073
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by ms6073

Unless some magnets have come loose, given how the Neo utilizes electromagnets and the significantly higher sampling rate used to calculate power output, I would accept the Neo over Stages or any other powermeter. That said, I have a v1 Neo and used to have an SRM Dura Ace powermeter and Neo power output was nearly always within 2-3 watts of the SRM. A couple years back GPLama took a tour of the Tacx manufacturing facilities and the video below talks to the process used by Tacx to calibrate the Neo.

Michael - The Anaerobic Threshold is neither...

petromyzon
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by petromyzon

There is absolutely no need to deal with "the inherent limitations of 1 sided power" as there are several sensibly priced spider and pedal options on the market. Stages' time in the sun is over.

AeroObsessive
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by AeroObsessive

nickf wrote:
Fri Jan 10, 2020 1:06 am
I did my first FTP test this morning. Buddy of mine uses a Tacx neo smart trainer. We did the zwift readout with the Tacx power on the screen. Stages was running on my Garmin 1030. The Stages was 40-50w higher the entire time. FTP Tacx was 245w, Stages for the same 20min was 308w. I did a zero calibration before the start of the ride on the stages. The Tacx nothing, just started the warmup/test. From what I have seen there might be a couple of watts discrepancy but 40+? My stages is only a couple of weeks old. I'm not so much concerned about the FTP number, I have no ego to feed but I feel one or the other was off. Which number do I build workouts on? I'm thinking I should follow the Stages numbers since that's what I own and thats what I will be using with a dumb trainer, when I pick one up. Maybe redo the FTP test with my trainer and the numbers off my stages?
Is this a single side Stages? If so, single leg power readings are less than useless, in the grand scheme of things.

Unless you have some other more reliable source of power readings my guess is the Tacx is more accurate. Inevitably, when faced with two power readings, usually the ego-denting one will be the right one.

spdntrxi
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by spdntrxi

^ you are all being a little hard on the single leg power meter group.. they are NOT less then useless..

I've done the DCR analyzer (DCRainmaker) before with my Stages/Neo/Vector. and they tracked well.. stages only would fall apart on a quick acceleration (sprint) because it lagged. Maybe the op can use the DCR and find out where it separates.

TobinHatesYou
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by TobinHatesYou

This is just a single anecdote, but my Stages is the least accurate power meter in my stable. I'm not even talking about it being left-only. Its left-only numbers do not match the left-only numbers on my Vector 2s, Vector 3s and Assiomas. All three of those pedals match each other within 1-2W at FT.

jfranci3
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by jfranci3

Did anyone mention the battery yet? High power numbers are either battery power level, battery contacts, or 0 offset.

spdntrxi
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by spdntrxi

jfranci3 wrote:
Thu Jan 16, 2020 5:20 am
Did anyone mention the battery yet? High power numbers are either battery power level, battery contacts, or 0 offset.
0 offset maybe... but generally battery issues involve power spikes of gynormous levels (atleast on the stages)

AeroObsessive
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by AeroObsessive

spdntrxi wrote:
Thu Jan 16, 2020 4:14 am
^ you are all being a little hard on the single leg power meter group.. they are NOT less then useless..

I've done the DCR analyzer (DCRainmaker) before with my Stages/Neo/Vector. and they tracked well.. stages only would fall apart on a quick acceleration (sprint) because it lagged. Maybe the op can use the DCR and find out where it separates.
Humans are by their nature, asymmetric. Unless you know exactly what that power asymmetry actually is at any given point of time you are *guessing* at the overall power output. The only thing single side power meters are good for are informing you of what your power output is for that leg.

Their best use would a nice looking paperweight. I would prefer athletes use no power meters than single side.

spdntrxi
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by spdntrxi

AeroObsessive wrote:
Thu Jan 16, 2020 5:57 am
spdntrxi wrote:
Thu Jan 16, 2020 4:14 am
^ you are all being a little hard on the single leg power meter group.. they are NOT less then useless..

I've done the DCR analyzer (DCRainmaker) before with my Stages/Neo/Vector. and they tracked well.. stages only would fall apart on a quick acceleration (sprint) because it lagged. Maybe the op can use the DCR and find out where it separates.
Humans are by their nature, asymmetric. Unless you know exactly what that power asymmetry actually is at any given point of time you are *guessing* at the overall power output. The only thing single side power meters are good for are informing you of what your power output is for that leg.

Their best use would a nice looking paperweight. I would prefer athletes use no power meters than single side.
I'm at my worst 52/48... usually 51/49 or 50/50. ... so I'm really not worried about my left leg power. To each his own.

AeroObsessive
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by AeroObsessive

^ you just described, along with the inherent variance of Stages, anything between a 2 - 10% variance of a given reading. If your 20min power was actually 200watts, this would give you reading of anywhere between 180 - 220 watts.

Next to useless.

glepore
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Location: Virginia USA

by glepore

spdntrxi wrote:
Thu Jan 16, 2020 5:53 am
jfranci3 wrote:
Thu Jan 16, 2020 5:20 am
Did anyone mention the battery yet? High power numbers are either battery power level, battery contacts, or 0 offset.
0 offset maybe... but generally battery issues involve power spikes of gynormous levels (atleast on the stages)
Yes. And as an example, all pm's can be subject to an issue. Everyone loves the latest garmin pedals, right? Google garmin pedal battery fretting. To their credit, they're sending out a fix, but I've seen some files with crazy spikes from fellow riders.

My take on stages-they're not as bad as people claim across the board. Bad ones tend to be bad, but the company strives to fix. However, the game is changing and they are lagging. They've recently had to do a major price cut. The spider based meters are falling rapidly in price, into single sided territory (although they're Chinese, they work). Would I buy a stages today? Probably not.
Cysco Ti custom Campy SR mechanical (6.9);Berk custom (5.6); Serotta Ottrott(6.8) ; Anvil Custom steel Etap;1996 Colnago Technos Record

by Weenie


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