I suspect that my power meter from the trainer and the pedals/crank are giving different readings.
I use three different bikes with three different power meters outdoors and a Tacx Neo 2 trainer indoors and have the feeling when i ride the same wattage outside with my Favero Pedals i have much more soreness after then inside on the trainer.
I’d have to put each bike on the trainer and see how much the power meter readings are different. But what could i do then?
Is it possible to use two FTP‘s with TrainerRoad?
It’s important that the wattage values are accurate so that the training intensity is correct.
How do you handle this? Do you have a solution for this problem?
I use 2 crank based (left side only) power meters (one Stages, one 4iiii) which seem to give near enough the same power readings.
My indoor trainer (Jetblack Victory) reads about 10w lower, I suspect due to leg imbalances that the other PMs obviously cannot detect.
For this amount I’m not that bothered. If it was 20w or more, I"d see if there’s some kind of adjustment that could be made to get the readings closer.
Road, TT, gravel, mountain, tandem, “bike path bike” and smart bike all with different power meters but they all feel about the same. Now I do have mad fits with the power meter on my wife’s e-bike which, curiously, are SRM pedals. Freaking drives me nuts. Sent them back for evaluation, SRM says they are fine but they just don’t seem anywhere close. So I guess I can’t help.
Actually….set the neo on a fixed wattage like 150 or whatever and ride each bike for like 15 minutes and compare the bike power vs the tax power then you’d at least have a relative measure of the three bikes
Create an ERG workout on Zwift/Trainerroad. Do this workout with all bikes/power meters on the trainer and record the power meter and trainer to different devices.
Upload and compare each pair of readings using zwiftpower.com/ analysis tool, and then adjust each power meter accordingly in the power meters app/software. (If the power meter does not have the ability to adjust the slope/power you bought the wrong power meter.)
Isnt it cool how all power meters claim to be accurate to 1 or 2%, but somehow irl thar doesnt work out. I have assioma, a kicker core and two new sram, and they all need to be adjusted. Live how dothe two new srams not match???
If one PM is 2% high, the other 2% low, that is 4%.
Then comparing pedals to spindle, you have more variability.
Wheel off trainer? Now you are adding in chain condition.
Let’s not start on wheel ON!
All three of my bikes feel similar enough that I don’t think about it (Vector, Stages, and 4iiii). But the wheel off trainer is definitely off enough that I can’t use those numbers. I tried.
I am in a similar situation. I have favero pedals on my off road bikes, a powertap hub on my road bike, and an old bike on my Saris smart trainer. The Faveros allow for adjustment in the app, so I put my pedals on my trainer bike and matched them using the power adjustment. I then put the pedals on my road bike to see how that adjustment compares to the powertap. Used it on my old dumb trainer at a steady state. It was close enough that I am not going to worry about it.
This topic is something I pay a lot of attention to. And I’m pretty much the same as @magnusc - The easiest option is to buy a power meter where you can adjust the slope / output. Adjust that power meter so it matches your trainer (up or down, doesn’t matter) and then you have consistency between the power meter and the trainer.
If you have multiple power meters on multiple bikes, you do this for every bike so they’re all matching. Basically, you use your trainer as the reference, adjust all the power meters, and then everything reads the same (within a percent or so anyways)
I use quarq on all of my outdoor bikes (which, you can adjust slope), and I have a set of Favero Assioma’s that I can swap around for dual recording (Or, triple recording!) to constantly compare outputs, and I can use these as my power meter on my dedicated trainer bike if I want to use power match.
I use @dcrainmaker ‘s analyzer tool - Basically I had it pretty good with my TacX Neo 2T, but I replaced it with a 3M that’s now reading 10 or more watts low in certain scenarios, but only off 3-4 watts in others.
Example with my XC Bike Quarq vs. the old Trainer:
