Saris H3 calibration

Hello all of you smart trainer users. I am hoping someone can give me some guidance:

I purchased a Saris H3 at the beginning of November, I love the Saris and it has worked flawlessly. The H3 has replaced a dumb trainer that I was using with a Stages Left crank PM. I did a ramp test a few weeks before getting the H3 and then I started having problems with my stages eating up batteries, this is partially why I pulled the trigger on the smart trainer.

When I first recieved the H3, I performed a spindown calibration using the Saris app. I then moved the trainer to the new room and continued where I was on SSBMV 1. I was a week in when I realized that I never re-calibrated the H3 after moving it, I also never did a ramp test on it and continued with the FTP I had from my Stages a few weeks before. I know that I made several mistakes here but after I realized my mistakes I reflected on my training and decided that the workouts I had been doing had me working in the HR zones I was expecting and felt about right, this is my third time through SSB, so I figured I had just got lucky and my trainer and power meter were close enough that I was in the clear.

I finished SSB1 at the end of the year and did my first ramp test on the H3 on Monday. I started out by doing a 10 minute warm up on the trainer and performing a spindown calibration on the TR app this time.
I didn’t pay much attention to the spindown numbers but I know the first value was 11 some seconds and the most recent was over 12. I did my ramp test using the H3 power and ended up with a 20 watt or 8% lower FTP than when I started SSB1.

I am just looking for a sanity check and trying to figure out what to do to keep my training consistent. I would be surprised if my FTP actually dropped 8% since I was coming out of my off season with no structured training. The reason I ask is because the FTP of 274 that I had been using for all of SSb1 seemed about right throughout the workouts, I haven’t tried a workout at the new FTP of 254 but I feel that it would be too easy if everything is truly constant.

So after this long story, I guess my real question is:

Has anyone experienced such a variation in spindown calibration results before? It seems to me there are a few explanations for the variance:

  1. My FTP dropped 8% during SSB1. This seems unlikely to me.
  2. My trainer got “Broken in” and now the power curve has changed somehow so I will be training at similar resistance but with different numbers.
  3. There is a large variation in calibration between the Saris and TR apps.
  4. The new value of 254 is accurate and I was not truly doing SSB workouts since I was over my threshold.

I am fine with a drop in FTP, I just want to make sure that I am getting consistent training going forward. I will try my first workout with the new FTP tonight which will hopefully shed some light on the matter.

I assume using power match with my stages would eliminate this entire fiasco so I am going to try to revive the stages tonight and see what the numbers look like compared to the H3. I may try messing witht he calibration spindown again too and ultimately will do another ramp test if I feel it is needed.

Any insight would be greatly appreciated.

A lot of people including myself are left leg dominant, e.g. 52/48, so a left-only power meter reads high.

A crank based power meter also doesn’t account for drivetrain loss.

On top of all that, power meters read differently to begin with.

I’d recommend mapping your Stages power meter against your S3. An easy way to do this is to put your trainer in Resistance mode and just start hitting arbitrary power numbers and holding for 10-20 seconds, almost like an accelerated ramp test. Record the stages data on your outdoor head unit while recording the S3 data in TrainerRoad. Then compare.

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  • Without a direct comparison between any power meter and the trainer, you really can’t say that.

  • What DID happen is you changed the tape measure you used between the beginning and the end of that phase.

    • Sure, it would be great if we could trust all power meters and smart trainers to be “accurate” and consistent with each other, but that is a pipe dream when you look at the range of results we so often see.
    • So, comparing data from one device against another, especially when you haven’t compared the devices at the same time, is not a good idea.
  • Your experience just reinforces the common refrains:
    1. Calibrate a smart trainer on a regular basis (2-3 weeks is commonly stated for wheel-off models), and anytime you move it to a different environment.
    2. Perform a new FTP test anytime you change the primary power measurement device.
  • That is best fielded by asking each company.
  • Adding my experience that I find Rouvy to be as good or better than the others for calibration. But no matter which you use, consistent use of the same app is a better choice than mixing (even though it might not really matter, I find it’s best practice to not introduce the risk of new variables).
  • Make sure to calibrate appropriately and you will be fine.
  • That goes to using the “same tape measure” and can be beneficial for using your inside training info for outside purposes. But do note that the variations from inside to outside often lead to different performance, even when you use the same power meter.

Overall: Variations exist. Nothing is as simple or straight forward as we’d like. So following known best practices and reducing the potential influence from unneeded variables is preferred.

Thanks for the responses. I realize the error of my ways and the implications of using two different “measuring sticks” but I am unsure of what my plan should be going forward.

I suppose I will just have to see how the workouts “feel”. I don’t want to re-do the ramp test unnecessarily and I plan on using TR to calibrate each time going forward. I suppose I will just have to go through a few workouts before I know for sure if my FTP is where it should be for proper training zones or if I feel that I need to retest. Hopefully I can get my PM working and start using power match so that there is no more uncertainty.

Are you racing the Dead Swede again this year Chad? If so I’ll see you there!

Thanks again

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I have a H3 as well. It is close enough to my 4iiii left crank after 5 minutes and the NP ends up being only a few watts different for the entire workout I don’t use powermatch anymore.

With that I recommend in my experince doing a workout and make sure it is completely warmed up. After that then use the saris or the rouvy app to do the spin down. It worked great for me this way and have not done another spin down since.

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Yeah, take what you have for info now and evaluate in your next few workouts. Adjust as needed if you think you are not where you should be.

I am doing that via an over-under workout after my Ramp test earlier this week. Will see what happens and adjust a bit if it’s off.

No hard plans on the Swede yet, but very likely to take it on again. I have a love hate with it (hate the descent on Red Grade), but it’s so close to me it’s about a must do event. I could try the 60 mile version, but will see.

What is your plan for distance?

I’ve done the 100 every year since it started in '17 so at this point I feel obligated. Red grade is definitely a beast either way you ride it but it’s hard to beat the view from the top!

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Thanks for the recommendation. I haven’t worried about the spin down much and wasn’t sure how long to warm it up for but after a workout is a good idea. I’ll have to try that next time!