How Important is Roller Inertia on the Turbo Trainer?

Triathlon Forum
1

I’ve got two fairly budget-level trainers, the Cycleops Fluid 2 and the Elite Crono Fluid Elastogel and I’m trying to decide which is best for my winter season indoor training. Apart from the frame design (which I won’t get into!) the main difference that I find between the two is the inertia of the roller. The Cycleops Fluid 2 has a fairly decent flywheel on it, so when you stop pedalling the roller still has a bit of momentum and typically takes a few seconds to spin down; the Elite is the complete opposite, has no flywheel and spins down almost immediately when you stop applying power.

On the trainer I like to concentrate on my pedalling form and trying to smooth out my pedal stroke (as per the TrainerRoad drills) and on the Cycleops I find this really easy due to the inertia of the roller. On the cheap Elite trainer it seems as though the lower inertia makes maintaining good pedalling form much more taxing and powering through that 5 o’clock to 7 o’clock zone at the bottom of the pedal stroke really gets the calves and hamstrings burning after a few minutes.

Obviously the Cycleops mimics flat outdoor riding the best but my question is, which is actually better for training effect? I’m inclined to stick with the cheaper Elite model because it feels like more of a workout, but will this ultimately benefit my riding when I get outside again in the spring?

As a side-note, using TrainerRoad’s Virtual Power the discrepancy between these two trainers is absolutely huge. On the Elite my FTP is 245W (3.77W kg-1) and on the Cycleops it’s 320W (4.92W kg-1), the latter of which I think is massive overestimation. I know TR say that you should be looking for precision rather than accuracy with Virtual Power, but that’s a massive difference to contend with if/when you switch trainers, switch to a proper power meter or for example if you’re using it for calorie burn estimation.

2

A trainer (or rollers) that mimic riding outside is my preference. I don’t think riding a trainer with zero inertia, even though it’s “harder” is of any additional benefit. it also sucks to feel like you are pedaling through mud.

As an example, I ride e-motion rollers for most of my intervals. i did a set of 2x20:00 on a kickr. It lacks the same inertia (though its’ better than most) that the rollers have, and my legs were sore the next day from a workout I’m never sore from. Different muscle firing pattern. I do not feel this is of any benefit whatsoever.

3

I see your point, but wouldn’t a turbo with high inertia only accurately mimic flat outdoor riding, whereas a low-inertia trainer would more closely resemble climbing? This is patently clear when you try to use the Cycleops for steady out-of-the-saddle efforts, where it feels as though you’re riding on the flat terrain and almost coasting at the bottom of each pedal stroke.

4

The high inertia trainer is probably still way lower than the inertia of riding on flat terrain or even climbing. The major difference is between almost any trainer and outdoors in almost any realistic condition with only minor differences between climbing/flat and trainer #1 vs. trainer #2.