Is it possible to adjust reported power from power meters?

I have 3 power meters and a Tacx Neo and they all report different power. Is there a way to adjust their reported power so I can get them in sync?

Tacx Neo - Let’s assume this one is correct.
SRAM Quarq Red AXS = +3%
Stages left side X9 Gen2 = +10%
SRAM Quarq XX1 Eagle = +11%

I swap between different bikes and trainer and want to be able to train on them without having to adjust my FTP-settings for every single ride because they report different power.
They all report consistent power, but the reported power differs a lot. Would be really nice if I could just adjust the reported power -3%, -10% and -11% so I could get them in sync. How hard can it be to make a feature like this available in the Stages and Quarq-apps?

Here are some comparisons I did with the power meters on the Neo:


They do not have to be 100% in sync, but more like in the same 2-3% range would be nice, so the TSS wont be ruined and I dont have to do different power in the same workouts because I use different bikes.


As much as it pains me to say it, given the differences, I’m not sure we can assume the Neo is correct.


I was convinced that my Neo was giving me low power until I got the AXS and it turned out that AXS and NEO was mostly in sync. I find it really weird that my two MTB power meters from two different manufactures (SRAM and Stages) are so in sync and still so far away from AXS/SRAM and Neo.

As long as these powermeters still are training equipment and not virtual racing equipment I wonder why it’s not possible to offset the power on Stages and Quarq.

I contacted SRAM support and got some help. Using the AXS-app it is possible to adjust reported power by adjusting Slope in the settings. This can be done in 0.5% intervals, so now my Neo and two Quarqs are in sync. Happy Quarq-days!

Factory slope:

Adjusted -12.5% slope:


Hello magnusc,
I am having the same problem you have:

  • AXS XX1 - +10% Vs NEO.

How do you adjust the slope down? It is just to push down -0.5 until you achieve the same two metrics? Do you need to do a lot of trial? Any guidance on process will be very helpful.

At the same time, any guidance from Quarq on why do we have this deviation?

Thanks in advance

Make sure you do the test inside on the roller. Do not compare your inside power to what you can do outside. Riding inside is very different.

If your AXS is reporting 10% more power than the Neo when using it with the Neo then you ned to tap the -0.5-button 20 times to get the power to go down 10%.

I recommend doing a new test on the Neo after you have done the Slope-adjustment to confirm that the changes had the effect you wanted.

I sendt in my Stages to Stages and they testet it and sendt it back with a paper confirming that it passed the test.

My conclusion is that power-meters and rollers are not very accurate at all, so virtual racing is not something I take to seriously.

Thanks for the response Magnusc.

I have tested my Neo against my Assioma pedals and both have same measurements, but at the time I do it against my Quarq Dzero XX1, my Quarq is up by 10%. I just want to have all aligned as it is a bit crazy to have different type of measures.

I will do the slope adjustment and get it along with my Assioma’s.

Any recommendation that you suggest me to do?

Thank you

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Does it make sense to adjust for L/R balance?

I know I’m 48/52 LR respective.

Given one of my bikes has a left-only crank PM, should I bump the slope adjust by 2% and then test?

Is anyone able to confirm that it’s still possible to use the SRAM app to change the offset for Quarq power readings?

Yes you can still adjust the offset in increments of 0,5%. You adjust the setting called Slope. I don’t recommend buying a power meter without this feature if you train with multiple power meters/trainers.

2 Likes has its own function to scale power by either a multiplier or offset… I wish that would be included in WKO5, because else the whole power duration curve is meaningless if I use my gravel bike to test…

After a year of confusion and frustration I finally discovered my Quarq was consistently reading 10 watts low outside compared to my Quarq on my indoor trainer bike. I was happy to discover I could adjust the slope and fix this issue!

Apologies if this is an insanely basic question, but the word “slope” implies that there is some exponential effect, and I just want to be sure I’m right. If P2M reads 5% higher than my Quarq and I want the Quarq to match P2M, I can either adjust the slope on the Quarq up by 5% or the P2M down by 5ish%. Right? Or is there some exponential effect here and it’s best to use trial/error to get them in line?

… bumping this up as it seems it isn’t as simple as just adding 5%… that seems to have sent me 10w / 4% too high.

Wonder if it relates to the offset number too. I’ve historically been ~-1050 but it was reading ~-1250 after fiddling with Qalvin (not sure if there is a relationship)

I upped it 2% to add about 10w if I remember. I tried 3% and it was too much, so 2% was low, but close enough. I’d try lowering your % until the power profiles match close at the powers you typically ride/race at. I tested my power at 150w, 200w, 225w, 250w, 275w, and 300w. Comparing the ride files I was within 1% at each power level.


If P2M reads 5% higher than my Quarq and I want the Quarq to match P2M, I can either adjust the slope on the Quarq up by 5% or the P2M down by 5ish%. Right?

Yes, that is correct.

How much 2% equals depends on what power number you are referring to. Saying that «2% sent me 10 watt higher» means nothing. If it’s while doing 100 watts it will be a big change, if it’s at 800 watts it’s nothing.

It is better to use a known mass and math than changing one meter vs the other. If you use a known mass and math, you can calibrate all of your power meters and keep them aligned to each other.

An issue is not all powermeter manufacturers make it easy for a user to determine the slope and push it to the powermeter.

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