Am curious to see whether there was any obvious power discrepancy between setups on my road bike vs more recently acquired gravel bike. Both have single sided 4iiii pm’s - one ultegra and one grx.
I have a chuck of data for both, so figured any discrepancy would be obvious in a power curve as I switched from one bike to the other last November. Is there a way to compare? I could use date ranges or gear (bike) but can’t see how I’d setup a compare.
I’ve seen a few related topics but not this exact one (I don’t think) so any pointers would be helpful even if to a related topic.
You can do that with 2 browser Windows side by side.
On the Power page, define filters for the activities you want to include. Filter in each window what you want to see.
I can see one other way to do this right now, but its’ a bit of a ‘hack’. That’s if you define the date ranges as ‘Seasons’. Then you would be able to see that in one PDC chart. The road bike results as ‘Last Season’ and the Gravel bike’s as ‘This Season’.
In my opinion, power curves is a very very rough way of comparing PM’s. I’d say that +/- 5% discrepancy between two is kinda on the verge of critical, and doubt that Power Curves can warant even that level of accuracy.
On a side-note… I happened to own three different 4iiii Precission cranks over the time, and when compared to a set of Vector pedals, all three were within 1-2% of each other.
If you want to compare more directly, you can use Golden Cheetah and set up separate athletes for each PM. Then you can overlay multiple files and even compare power duration curves from each meter.
That’s how I used to compare the spider, hub, left crank, pedal, and smart trainer power meters when I was running 5 concurrent meters.
With the indoor cycling software from www.icTrainer.com you can, for example, run two power meters in parallel during an indoor session and evaluate the comparison (find out more in the tutorial video ).
As a side note for this, my PM packed up for a couple of days after use in heavy rain.
It read over 1,000W high (I wish), failed to calibrate and then read 0W. Cadence was OK and the ‘find my’ feature ok.
After a few comms with 4iiii, they were about to replace it under warranty, but then we tried the last thing which was to leave the battery cap off overnight, and also I blasted it with a hairdryer, just incase water had got in.
Low and behold it was back working the next day.
So I have to say at this point 4iiii were a little defensive, talking about replacement seals, greasing the seal etc etc - all on a 3 month old £400 PM. So I suggest that perhaps they’re not as waterproof as they should be, at least for getting caught in huge downpours. Bit disappointed in that but I’ll keep any eye on it, and maybe this note helps someone in the future.
Sadly the dropouts and spikes returned and has now gone off for warranty replacement (hopefully).
Not sure whether it’s just not designed well enough for wet weather or was just unlucky. My ultegra one was faultless but I rarely rode in the rain or wet on my road bike. It’s not like I try and go out in the wet on the gravel bike but it’s certainly seen a fair share a heavy rain and puddles.
Bit frustrating but will just enjoy riding for a few weeks and not worry about numbers……
Load a workout in the app on your PC (I was maybe using BigRingVR, can’t remember). The app controls the HT and records the ride in ERG mode. Another app on your phone records the power from your external powermeter.
Change bike, do the same workout with your app and phone.
Compare the resulting files.
Luckily, the powermeter I had causing some trouble is a XCadey. They have an app to “calibrate” it.
It now appears stuck in the slowest warranty process - having been told by 4iiii it most likely needs replacing it’s gone back to the trailer then back to the U.K. distributor for checking where it’s apparently languishing in their tiny office in some industrial estate in the U.K. meanwhile 4iiii just ignore me. Glad I spent months dealing with them diagnosing the issues and sending screenshots of all the dropouts in workouts……
I’ll replace it with the new Assioma mx-pro pedals and hopefully have better luck there.
Rant over.
But meanwhile my fitness graph has plummeted.
Admittedly I have had a recovery week, but since having no power meter the past few weeks the fatigue upticks from heart rate only workouts seem far less generous than power based workouts and so in graphical terms my fitness has really dropped. Fingers crossed my actual body isn’t doing as badly.
