Is it me or my power meter?

I’m kind of at a loss here and I wanted to solicit the opinions of you all.

A couple weeks ago I took a new FTP test and got all the way up to 356, did a couple TR workouts afterwards and did them with no problems. Then I went on a trip that I could bring my bike, so I took off my pedals (Favero BePro) but had some issues with my right one. I had the hex wrench in there and actually tightened it when I should have been trying to loosen it. Whoops, my bad. I did get them off though. On my trip I did a couple “fun” outdoor rides where I wasn’t exactly training but wasn’t going easy. (I did some KOM hunting and bagged a couple. Yay!). It was a pretty stressful trip where you could say I was doing “trade show” type stuff.

When I got back a couple weeks later, reinstalled my pedals, and put the bike back on the trainer. Once I resumed training I was having major issues even getting a couple minutes into a VO2 Max interval. It felt like I was pedaling through concrete. I did a zero calibration like always, did a spindown on my Wahoo Kickr, and did the BePro backpedal calibration as well. Still felt way too hard. So I figured maybe my legs were just tired. But this has been going on for about 10 days now, and even when I do an endurance ride around 230-250W I’m struggling.

Normally I would say that I’m overreaching and need rest, but I’m a triathlete so I’m also running and swimming. Those two sports I’m not seeing anything degrade with regards to my performance.

Then last night I was supposed to do “Jacks” which are some longer intervals slightly above FTP. I lowered my FTP to 330 manually just in case I had de-trained a bit. Calibrated everything. Then once I got into the interval I couldn’t keep moving the pedals. Everything was saying that I was around 310-340 Watts but it felt like 450. Eventually I set the trainer to Standard and did the workout based on RPE. When my RPE felt like I would expect a slightly above FTP effort my power was hovering around 240-260. Still, my HR was around what I would expect for that kind of wattage.

So, do I need to rest my bike? Rest everything? Get a new power meter (did I damage them my tightening too much?), Suck it up and suffer properly?

Thanks for your help.

You aren’t 100 % clear what power meter you are using indoors, but I assume it is your pedals, correct? If that is the case, I would get both power numbers side-by-side, e. g. switch TrainerRoad to use your Kickr’s built-in power meter and compare those power numbers to those of your pedals (displayed on your head unit or smartphone). If they diverge by as much as you feel they have, then I’d say you forked one of your pedals. Perhaps you can get it serviced or the manufacturer will offer you a deal to get one replaced. I don’t know.

If you want to be more thorough, re-establish your FTP using the Kickr’s power meter. It is unlikely that you will get the exact same power numbers, but they should be in the ball park.

Yes, I’m using Favero BePro pedals as my power meter. I forgot to mention but I did have the Kickr power up as well looking at that side by side last night and they were pretty similar, but realized that I had powermatch on. Not sure if that affects things as well.

Also, I’ve got an Olympic triathlon this weekend. I’ll bike on RPE and if I get that portion done in say 1:00 on what feels like 300W, but my PM shows 220W I’ll know it’s the PM for sure. But if my time is 1:15 I’ll know for sure it’s me, which is what I highly suspect. But what’s really odd is that my running and swimming is just fine…

First, I’d try to eliminate your pedal-based power meter from the equation, at least indoors. Switch off power match and take an FTP test. Try a couple of workouts and see if your perceived exertion corresponds roughly to the difficulty of the workout. Perhaps a workout with short threshold interval (of 90-100 % of your FTP) might be a good way to gauge whether you tested correctly. Perhaps it is your initial FTP that was faulty, because your pedal-based power meter was initially not giving you correct data. And after re-attaching them, you are finally getting more accurate data from it.

(When I first got my 4iiii power meter, I got fantastic power numbers for first few rides, I spent 20 minutes at 415 W during a mellow ride. I had followed the installation instructions to the letter, including the torque specs. I went on a trip abroad for about 4 weeks, and when I returned I got realistic power numbers, despite (because of?) not touching the bike in any way.)

Also, I like your suggestion outside, if you ride a course that you know very well and you know your times, then you can estimate your power off of past efforts that had good power data. But when your pedals and your Kickr roughly agree, I would still think your initial power numbers were wrong.

Could you not use the trainer and pedals independently and side by side to compare?

Ie connect the trainer with TR and the powermeter pedals with your head unit and compare the 2?

That seems like it would be easier than using one at a time and comparing it with feel or doing a ramp test


It sounds like you have two devices that can measure power, the Turbo and Pedals. Both should be within 5%.

Setup a simple TR workout and pair one of the devices. Then pair the other device to your head unit. Once you are finished compare the power data from both rides. They should be very similar and you will spot any big differences.


I recommend:

  • Trainer paired to TR app/device
    • Make absolutely certain that you unpair/forget your power meter in the TR Devices page.
  • Power meter paired to head unit
    • Likely already setup this way for easy connection.
  • Check power data smoothing on both and keep that in mind if you are doing a simple A/B comparison between the powers.
    • If you maintain a smooth and steady power, it may negate the smoothing, but the nature of the difference in the power measurement between the trainer and power meter can still cause some notable variations.
  • If you haven’t already done so, I recommend turning off the “ERG Mode Power Smoothing” setting in the Wahoo app. It will give you more realistic power data compared to the artificially smooth default from Wahoo.

After a number of experiments both inside and outside the definitive answer is…my power meter.

One of the things I realized late last week was that when I was looking at the Wahoo power, it was on the TR pairing screen, and there the two looked to be in pretty close agreement. What I eventually realized though was that included the powermatch. So those were not the correct numbers. I worked with TR support and they were able to get me the PowerMatch offsets from a workout this month and last month and they are substantially different. (35W or so).

Then I did my race, where I averaged 37km/hr on some poor pavement with some hills at 232W average. Now I’m a 193cm 88kg guy on an aluminum road bike with clipon aero bars. Either my CdA is somehow around 0.24 with a pretty low Crr according to Best Bike Split…or my power meter is messed up. (I won the triathlon BTW…first race I have won outright so very happy about that)

So then last night I did the final test. I unpaired my power meter from TR, calibrated EVERYTHING, and did Dicks +1 (5x8min at 105%FTP). I recorded my ride in TR using the Wahoo, and on my watch using my power meter, and I looked at the average power for each segment. During the intervals, if I averaged 320W on the Wahoo, my watch would show I averaged 260-240W. If I averaged 120W on the Wahoo during the recovery, my watch would show I was averaging 20W!!! A couple times I really bumped it up to around 400W on the interval, and my watch would show around 300W. It wasn’t even following a linear pattern. It was just all over the place and not entirely consistent, but the Wahoo felt “right” from what I expected.

So last night I broke out the CC and ordered a new PM.

Thanks for the suggestions everybody.


Seems like you solved the issue. For future reference, the pointiest end of pointy-end triathletes are usually around 4.5 - 5.0W/kg at FTP (we’re talking multi-time Ironman winners here), so if you’re strictly a triathlete (without a Cat 1/2 bike racing background, for example), and you’re testing at 4.0W/kg+ at FTP, you are probably winning local races overall or at least winning the bike leg, and assuming you can swim and run respectably there’s a good chance you’re qualifying for AG world championship events pretty consistently. If you’re not performing at that level with that kind of FTP, something is either way off with your racing or off with your measurement.

I won my local “Oly” on Saturday with the fastest bike split, and took 3rd in the 35-40 AG at my area’s biggest tri, all with my Caad10 and clipon aerobars. So that’s part of the reason I was thinking it was the PM. :slight_smile:

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Niiiiiice. Part of what brought me to TR was that I’ll podium most sprint/oly and local races, but when I get to bigger events (e.g. IM-branded, AG nats or worlds), I’ll have a decent swim and a good run, but I was getting smoked on the bike leg by the podium guys. About 10 months into my bike-focused year, I’ve gone from 3.4 to 3.9W/kg. If/when I get back into racing tris, I’m hoping I can hold that fitness and exploit my other strengths to find my way up there for 70.3 worlds spots I’ve narrowly missed and eventually Kona when I finally go really long.