How much does the flywheel weigh? It's a question we're asked often, and rightly so – a heavy flywheel matters a great deal to most users. The reasoning used to be: the heavier the flywheel, the smoother the rotation, the more pleasant the session.
For traditional machines that generally still holds. You'll often see cross trainers with a flywheel weight of up to 25 kg, for instance, or exercise bike flywheels of 10 kg.
The Nautilus, Schwinn and Bowflex cardio machines, though, all have a far lower flywheel weight. The Schwinn 590U exercise bike, for example, has a 4.5 kg HIIT flywheel. And that isn't only because it's a distinctive movement. The Nautilus E628 cross trainer has a 4.5 kg flywheel too. So are these machines less effective? Does a machine feel less smooth if it has a light flywheel?
Does flywheel weight matter?
The weight is one of the most important specifications to look at.
The thing is, Nautilus, Schwinn and Bowflex flywheels are designed differently. There's the mechanical design of the rotation point, the distance from the magnets to the flywheel, the magnet Gauss rating, and so on. All of these components contribute to the drive system.
Change the pulley dimensions and the gear ratio and that affects the flywheel too. A traditional flywheel has a 304 mm input pulley. Nautilus, Schwinn and Bowflex use 330 mm, which gives a gear ratio of 11:1 against the traditional 9.6:1. Because that ratio is higher, the flywheel can turn faster, which in turn produces kinetic energy. Thanks to that ratio, they increase the energy generated by almost 3 times at the same revolutions per minute (RPM). That's what you call a smooth movement. So the exercise bike with a heavy flywheel becomes rather less important.
Last but not least, they choose to place the mass as far towards the edge of the flywheel as possible, which produces more kinetic energy again. It's a fairly complex process. If you'd like to read more about it, it's worth searching for "moment of inertia".
Here's the formula:
Flywheel weight: the verdict
There's more to it than the weight of your flywheel alone. At Nautilus, Schwinn and Bowflex they talk not about one component but about the complete system, which they've optimised as thoroughly as they can. The MY13 drive system delivers a simple, quick start. The rotational kinetic energy produces a high level of performance with less weight. All of this contributes to an effective, comfortable, enjoyable training experience.
Want to know more about these innovative brands? Take a look at their full ranges through the links below:
