My DC Analyser Data

Hi All,

Hoping someone can help me understand this and determine what I should do for future TR sessions. I have been using power match with my UNO and smart trainer but its very bumpy for VO2 max and threshold intervals. Big extended spikes as per the snip below.


DC Chart…

The DC Analyser shows a comparison of my Favero UNOs (via Garmin) and my Bkool Smart Pro 2 Trainer (via Zwift) during a Zwift ride. The obvious issue here is that there is a 10sec delay comparing pedal power to trainer power. This makes sense as the trainer needs to adjust resistance when I put the pedals down harder/faster but seeing this makes me think i should just ditch power match and use my trainer only for TR. Having Power Match calc’ing averages of both is probably giving me a wilder ride…especially with the left leg UNO power being doubled and the clear delay in the trainer reacting to resistance changes / interval step ups etc.

Guessing my trainer power lines are smoothed out quite a bit but overall the power comparison to the UNO is ok.

Does this make sense…am I interpreting this correctly? The analyser tool time matches the data so the 10sec delay can’t be from misaligned charts.

Any comments / suggestions would be appreciated.


OK erm…figured it out. Turns out there was a time offset. The cadence and HR data were offset which isn’t possible.

Put in a 10sec offset and got this below chart which isn’t to bad. Power is reasonably close so I’m better off sticking with trainer only in my case.

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Based on my experiences those traces look very close for a single sided power meter. Admittedly I have quite a large power imbalance. I have to offset my single sided PM by -12% to get them to line up. It’s almost as if you were using Erg,

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If you plan on doing any outdoors work outs you may be best ignoring the trainer and using the uno in (via powermatch) and out :+1:

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I don’t know about “better off”, but it appears that you could use one or the other and all would be okay.

Personally I would keep on using the UNO w/Powermatch. The UNO is what you will be using outside. This way your power numbers are from the same source both indoors and outdoors making them 100% comparable. Yes, it appears you could could just use the trainer and ditch Powermatch, but using Powermatch isn’t costing you anything.

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Thanks for the comments. I agree that sticking to the UNO / Powermatch would often be the best option as I do complete some workouts outside (in UK Summer).

My main issue with powermatch is the variance I see during VO2 max and threshold intervals. For example it has had me at 150% FTP for the first 30seconds of a 1m30s threshold interval which just wrecks me. I then need to reduce intensity at some point to complete the session.

If anything the DC tool has made me less concerned about the power differential between the two sources. Considering this I know i’ll get smoother sessions / intervals with trainer only and I can always do a pre-summer ramp test with powermatch just to confirm numbers.

Are you using the ‘new’ Powermatch or the old one? The new one seems a bit less erratic. My observation is a smooth, fast ramp-up in the first two seconds followed by an overshoot. Then it settles down and bobs back and forth across the target line. The overshoot is not as bad as the original PM and it settles within 5-6 seconds.

Example: I did a series of 115% 1-minute intervals last Friday. In each I ramped up to the overshoot in 2 seconds. My interval target was 273 and the overshoot peaked out at 315. By 8 seconds in, I was near target wattage and proceeded to bounce back and forth over the line to the end of the interval. I ended up with a completed wattage of 270 for each.

Remember, you are using a one sided power meter. Hard to say conclusively that you are really overshooting that much for that long. One leg is likely to be dominant especially when applying power to get up to speed or in this case target power. :man_shrugging:

If you want to smooth your power out, especially that spike, you need to smooth your cadence out. About 15s before the interval starts, get your cadence up to whatever you are planning on doing during the interval and when the resistance hits, try to stay smooth and maintain the same cadence.

Pardon my ignorance, but what is the “new” powermatch? On my Samsung Galaxy S9, I see only one option for Powermatch, and on the TR workout page, it says that my power source are my “Favero Assiomas”.

It’s in the beta software and I believe it is currently limited to IOS. They are still tweaking, but I can tell you that it is so much better than the current GA version. If you are having PM issues, hang in there.

You can apply to get into the beta program m. I think that the TR website has a place for that. Otherwise you can request it through the forum.


I have signed up for the Android Beta, but have no email from them on that yet. Will wait.