Garmin 945 reads higher power than trainerroad

I just got my SRM power meter back from getting a new battery and getting tested out. I also just started measuring the SRM power simultaneously with my Garmin 945 watch and with Trainerroad (not in erg mode, but in standard mode with my KICKR). I calibrated the power meter with both the watch and TR and got the exact same offset, yet when I pedal, TR is reporting that the SRM is sending power data that is about 25 Watts lower than the Garmin 945 at power readings from very low (50w) to at least 225w.

I tried switching the watch between smart recording and 1 sec recording but the difference remained. I also told TR to “forget” my KICKR but that had no effect on the monitoring differential.

I am using a 2015 Macbook Pro with an ANT+ dongle on a six inch extension cable.

Has anyone else ever seen this?



Are you 100% certain your watch is paired to the PM and not your trainer? I also have a FR945 and it can occasionally be a bit tricky as it will pair with the trainer before the PM. Essentially had to remove the trainer from my device list to keep it from doing this.


Yep, I would also think that the two devices are not paired to the same power source. The power meter sends out one signal, so each device will get the same information. It could be that if there is a large difference in eg smoothing that you see slightly different values, but I can’t see that being 25W.

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I agree that they are probably getting power data from different sources. I recently bought a 945 and have been running it alongside TR with a stages power meter. I haven’t been looking at the power data during the ride much but afterward the IF, TSS, etc are all within like 1% of eachother which can usually be explained by the fact that TR pauses when I stop pedaling but the Garmin doesn’t.


I always dual record TR & on Garmin and I find the Garmin data is almost identical to TR as well, minus the occasional start/stop timing.

Thanks for the comments everyone.

Since the watch was showing 25 watts higher than TR that makes me think it was reading from the crank SRM power meter. I would have expected a slightly lower reading if it was reading from the KICKR. This is what I saw, by the way, when I compared the KICKR power vs. the SRM power in TR.

I’ll try clearing all the power meter sensors from the watch and pairing it again with the SRM, with the KICKR turned off to make sure that it isn’t pairing with the KICKR.


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The other note then would be make sure TR is set to powermatch your SRM and not just on cadence only. Otherwise TR will be readin power from the KICKR which could also explain why the watts were lower on TR if the watch was paired correctly.

How are you seeing this discrepancy? In real-time? Or are you recording both sessions and then using a tool like the DCRainmaker Analyzer tool?

If you are looking at the real-time power numbers, and not analyzing a full ride, try analyzing a full ride and see if the FR945 file is constantly higher. The other reason for analyzing a full ride is that the FIT files should indicate the power source, so that would be another way to make sure both are recording the SRM.

Problem solved! It turns out that when you calibrate your power meter with the Garmin 945 watch, you need to accept the current calibration value that it is showing you. I’m wasn’t apparent to me that I needed to click the button at the two o’clock position to accept the value.