The only time I’ve heard “don’t use the big ring” (on a smart trainer) it was for noise control. This was in a group setting, with 15 trainers running in the back of the LBS/cafe.
Then you were misinformed.
Noise level is higher at higher gears. This can come from the trainer, like the older Kickr’s and any with the cogged belt/pulley designs. The bike drivetrain also gets louder as it spins faster. But unless you have a nasty drivetrain, most fans are as loud or louder. With the advent of the newer trainers that are nearly silent on their own, noise is not much of a concern unless you have one of those older trainers.
Another consideration for gearing is that many trainers have some power data deviation in higher flywheel speeds. I’ve seen it for the main ones (Kickr, Neo, Hammer). As long as a person is consistent with testing and training in those higher gears, I think it is fine. But it is an interesting aspect that doesn’t get mentioned often.
1 Like
Ive not heard don’t either, but Ive read TR recommends small (with ERG), maybe that’s getting interpreted as a don’t… Personally I would prefer the big ring for inertia at threshold but its too noisy for my neighbours up stairs of my tiny flat.
Set your gearing - In order to maintain smooth, even power across all of your power zones, you should maintain a mid-ring gearing in the rear cassette, and either a mid (if you have three) or inner (if you have two) front chainring. Your chain should follow a straight path from rear to front. This will also help you avoid hitting a wattage floor. When in doubt, check your Trainer’s manual for their recommended gearing settings or reach out to us.
2 Likes
That is exactly what I thought because on a ‘smart bike’, it’s all ‘artificial’; meaning IT chooses the ‘ideal’ speed of the real, or emulated flywheel. I remember, years ago, someone on FB bearing down on the whole virtual flywheel of the 2T, and people said to ‘just relax and ride’, and let the trainer figure it out.
Tacx’s virtual flywheel is a discussion entirely on it’s own from this one. It has some unique attributes to how it functions, which may or may not align well with the physical flywheels in all use cases. No idea if it’s better/worse, but from my experience comparing my Neo 2 to my Kickr’s and Hammers, they are different 
1 Like
And that was one of the reasons I was told to ride in the small ring. I did feel that the H2 would ‘float’ over shorter lower intervals, and at the end of a higher demand interval it would take some time to spin down to the current demand. (At least it felt that way)
The noise was excruciating with the H2, the wife said she could hear me riding from the garage, which was 2 rooms over. The H3 is like a totally different world in noise. The H2 drowned out darn near everything in the room and the only way to live with it was noise canceling headphones. OUCH!! I went from the H2 to the 2T, and got an H3 for a spare. The wife was surprised for the first couple of days, felt like she was sneaking up on me. Hah!
The H2 was somewhat quieter in the small ring, but still noisy. Can’t say I miss it.
1 Like
@BTTG, after looking at the image you’ve provided, it doesn’t appear that this is likely a wattage ceiling issue, as your power ended at a level lower than some of the averages of the previous intervals. I’m not able to see a ride log for this one, but logging out and back into your account should push the data over to our servers to see. Let me know once this is done, and I’ll take another look.
In regard to the discussion around gearing choices, we recommend using lower gearing (small ring up front with a straight chain line in the back) for the best user experience with smart trainers. The goal here is not necessarily to replicate the exact “feel” of riding outside but to sharpen the responsiveness of resistance from the trainer, especially during large changes in power for short durations of time (think microbursts or “on-offs”).
When the flywheel is spinning quickly, it takes longer to settle into the prescribed power target after a jump/drop in resistance. Think of this as applying the brakes to a car moving at 60mph vs. 20mph. The faster car takes a bit longer to slow down.
The inertia of the faster spinning flywheel when using a big gear feels to us more like riding at a high speed on the flat ground, whereas lower gearing/flywheel speed feels closer to climbing. You feel like you’re muscling through more of the pedal stroke.
Some users might prefer one feeling over the other, and in my opinion, pedaling at a given power does feel marginally easier in a bigger gear, but my priorities are trainer responsiveness and nailing the intervals at the prescribed power, which is more likely to happen in a lower gear.
8 Likes
Yes! My first couple of rides on the 2T, I kept wondering what the flywheel was simulating. I never seemed to ‘feel’ the flywheel effect as much, if at all. I’m sure it’s there (Garmin says it is 
) but hmm…
Yeah, when everything is virtual, it sure can warp the mind if you spend any time thinking on it. At least it does for me. 
Who knows what’s real when it has such a potentially large artificial component.
We should all just ride and be happy, right. Don’t ask many questions. Okay… 
That’s what I remember: USE THE SMALL RING. Some other people online and IRL said the same thing: Use the small ring. Pre-Saris Saris said the same thing. ‘I’m not crazy, my mother had me tested’.
1 Like
Eddie,
I logged out of my account and then logged back in so my data should have pushed to your servers.
Thanks for your help.
1 Like
@eddiegrinwald ^^^
2 Likes
I am not sure if it’s the same thing, but I had a similar problem during a workout. Power stayed constant: it did not increase during intervals and then stayed high during recovery. My best guess as to what happened, after talking with support, is that my computer which was upstairs had the TR app opened and stole the Bluetooth connection from my phone, which I was using at the time.
That is a big ups for most of us. I have a 1x mtb system on my trainer 
Too bad devices with gigantic fly wheels also suck at other functionality (noise, reliability, accuracy).
What can we do other than ride outside as much as possible?
I have been using my Velodyne trainer about 200 h/y since 1989 - long enough to have worn a distinct divot in the steel roller against which the tire presses. (Reliability? Check.) It has always aligned closely with various power meters I have owned. (Accuracy? Check.) It is also reasonably quiet, at least quieter than the large floor fan needed during indoor training.* (Noise, or lack thereof? Check.)
My point is that it has long been possible to build a trainer that meets these criteria - the reason manufacturers have gone in other directions is entirely because people haven’t demanded them (just as CompuTrainer was able to sell thousands and thousands of trainers even though their accuracy was horrible).
*If you’re not using a large fan while training indoors - while also keeping the room quite cool - you’re doing yourself a major disservice. Save the heat acclimatization sessions for when they are needed.
Otherwise, yeah, ride outdoors as much as possible, ideally frequently with others.
1 Like
I guess we are going down the rabbit hole.
What I do not like about those big “smart bikes” is being vendor locked in terms of power measurement. If that BH is crap in terms of accuracy, and I bet it will be, there is nothing you can do about it. I have to use pedals and ignore the SmartBike generated power. Ok, fine. Then I am paying for the silence, fly wheel size and saving my nice bike. Which frankly does not worth that much money.
And there is the problem of virtual racing if you are into that kind of a thing. Yes, it is a game and nobody cares but if you are into it those Smartbikes will create only problems. They measure low, you will be smoked. They measure high, you will be disqualified. Not nice if you are representing your real identity online. Your dual recording, however low a bar to pass, will be a laughing matter.
If you go to the big name Smart bikes they cost a lot, some are ridiculously inaccurate, and some are not reliable enough for the money.
Best bet for serious races is using a deadbeat bike with cheap but compatible with you know what trainers. So when they crap out you can just buy another one. And can dual record with two of your own PMs if needed. But those trainers (Zwıft hub, Kickr core etc) have very small flywheels.
Hence the dilemma.