Do I need to power match?

Hi all, I think I am having a hard time understanding this topic…

I use a Wahoo Kickr new version paired with either an iPad or iPhone that runs the TR app, and I am always in ERG mode.

I have a Wahoo Roam and just bought a Favero DUO power meter to use for outdoor riding.

My question is if my indoor Kickr with its own internal power meter says my FTP is 236W via a ramp test, then can there or will there potentially be a power discrepancy when I use the DUO on my outdoor riding? Meaning, maybe the DUO and the Kickr internal PM do not match where one will say 236W and maybe the DUO will say something a bit different?

Is this where I should use the DUO on my Kickr set up in Power Match and do a FTP test and then get the result and then use it on my outdoor riding?

Sorry, confused…

Oh in addition, when I have the DUO hooked up with my Kickr, the TR app does not show the power reading… I have it paired with my Roam but then it happens with either the Roam on or off… no power reading in the TR app even though the DUO is properly set up in TR Devices…

In theory at least, your pedals will measure about 4% more power than your Kickr simply because they are measuring your power up-stream of your drivetrain (you lose approx 4% of your power through your chain drive). But on top of that you also have tolerances in both power readings, typically +/- 1-2%.

So in short they are unlikely to read exactly the same and it is more probable that your DUO pedals will read a bit higher if both are well calibrated.

If you want consistency across indoor/outdoor training, then Powermatch is probably the way to go. But I don’t use it myself. I just know that my outdoor power meter reads a few percent higher and don’t worry about it. For me it’s less than 10W difference in average power on a typical multi-hour ride. While that is significant it doesn’t really affect my power targets on the bike. So if I’m targeting say 240W on a climb, it doesn’t matter so much if I’m 10W up or down on that. But I am aware of the difference and psychologically it kind of helps having a very slightly higher outdoor power reading!

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This!

Also regarding the power not showing - do you use bluetooth or ant+? With bluetooth, you can only connect to one device at a time, so if your roam is connected, TR on your phone won’t see the Duo’s anymore. If you switch it over to ant+ you can have as many devices connected as you want. You could eg have the duos talk to the roam via ant+, and to your phone via bluetooth (i your phone can’t do ant+.

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Thanks for the clarification! So long as I am within a few % then all good.

No idea, sorry. Maybe ask support@trainerroad.com?

Sorry, my fault, it works now. Thank you.

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I had it loaded in my iPad Wahoo app… I thought I had it deleted… Now it is working in both the Roam (via Ant+) and TR. Thanks!

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I finally got the DUO set up (thanks Splash) and you’re right, it’s not for me.

The Roam has a 3 second power smoothing and not sure what it is for the TR app (setting to 0.5?). Sometimes the 2 readings looks good, sometimes way off. The TR app power output number is also jumpy, but expected. I’m pretty sure both the Favero and Kickr PMs should be pretty close to each other and as you noted, there will be the driver train difference.

Currently I am doing Polarized training. So, I will do my 2 or 3 VO2 sessions indoor and do my recovery and my Zone 2/5 rides outdoors so that means I just need to stay under or near my Aerobic Threshold and I’m a happy guy. For that, I don’t need all the headache. :smiley: Tanks for the help!

FWIW, I have the exact same setup (Kickr and Duos) and do not use PowerMatch. My pedals and trainer consistently read within +/- 1% so I use TR paired to the Kickr, and dual record the Duos on the head unit. That way I can compare the two power sources to each other to determine if one starts to have problems. The pics below are from two previous rides, and it’s typical for larger discrepancies at very short durations.

If the trainer and pedals were further apart then I would use PowerMatch.

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Thanks! Good to know this.

I have the same setup and do use powermatch. TR uses the duo. I want my indoor and outdoor to feel the same. Some don’t. Even then, there is a slight power difference outside to inside. Probably mental.

Will it change your ramp test ftp, yes. But then again, ftp is just a number so as long as you keep the setup consistent, train away. :slight_smile:

Thanks for the input. I am curious on how different will my ramp be. As Peteski mentioned, there is the driver train differential and maybe a bit more due to equipment tolerances. Maybe in a few weeks when I am ready to do my next ramp, I’ll do one with the Kickr only and one with the DUO on the Kickr and see how the results compare. As written before, with a Polarized Plan, my outdoor rides will be just Z2 riding so anywhere between 65 ~ 78% of FTP will be fine.

I would simply dual record a single ramp test and compare the resultant power traces back-to-back. If you do two separate ramp tests there will be likely more variation in your own testing performance than in the two power measurements.

For riding outdoors in Z2 it really isn’t going to make any difference unless your Kickr or pedals are faulty. But I do find dual recording my power meter and trainer power very reassuring that both are providing reasonably accurate numbers. It takes away that nagging doubt you always have with a single power source!

Take the duo by ant to your bike gps. Take TR to your kicker. Record at same time. You will see differential, in my case about 8 watts.

Thanks! I had a brain freeze and didn’t consider dual recording!

I have the same setup and found my kickr to be reading as much as 10% high. This doesn’t mean to say yours will be but if you want to use indoor power readings to set outdoor intensity levels, I’d definitely power match. For me the drop hurt but I’d rather know the true reading. Good luck :+1:

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Thanks. I am OK with FTP drop or gain. At my age, I am happy just to maintain. What’s important to me is to know how my Kick FTP translates to Favero Duo read out. My main point is to know my FTP on the DUO and then get my Aerobic Threshold so I can do Z2 training outdoors.

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