Flywheels have transformed the indoor cycling experience. With this simple piece of hardware and some smart engineering, we are now able to offer an immersive, realistic experience that is incredibly close to road riding.

First things first. What is a flywheel?

Developed in the 1970’s when isoinertial exercise machines were invented, the flywheel has become one of the most important parts of modern smart trainers.

Essentially discs that spin, conserving energy and momentum, flywheels closely emulate that road feel in modern trainers where momentum carries you forward.

When you stop pedalling on a flat road, the bike will still continue forward for a short distance. It’s this kinetic energy that is simulated by the flywheel. And the heavier the flywheel, the more realistic the effect.

It’s a difficult balance though, and often proves a delicate engineering challenge. Too heavy, and it becomes difficult to get going, while too light and momentum is immediately lost once you stop pedalling.

Adding resistance

So flywheels keep you going, but when you’re indoors without wind resistance, friction or gravity, what slows you down? Indoors, cyclists used to rely on rollers (friction) or air-resistance trainers. The main drawback was that the only way to alter resistance was by changing the gear on your bike. Peak resistance was easily reached which resulted in less effective workouts, especially for those doing high-intensity intervals.

There are many solutions for adding resistance. At Tacx, we use magnets. Magnetic resistance is a highly functional, maintenance-free solution that provides consistent accuracy. Coupled with smart electronics, they have opened up indoor training to a whole new world of dynamic control and interconnectivity.

Virtual flywheels are the future

On our line of trainers at Tacx – the NEO 2 Smart and Genius models – we’ve gone beyond the standard flywheel, replacing it with an array of magnets to create a ‘virtual flywheel’ resulting in an incredibly realistic riding experience.

The enhanced online user experience is the result of software simulating the actual conditions via dynamic control of the flywheel. The software can factor in other parameters such as rider weight and gradient, dynamically altering the resistance.

In short, it all means that when the gradient in the virtual environment changes, it will automatically feel more difficult on the trainer. The heavier you are, the harder it will feel. This results in a greatly enhanced indoor cycling experience that’s tailored to the individual and the conditions. And it’s all thanks to the magic of the flywheel.

Indoor cycling and the online world go hand in hand. It’s that symbiotic bond that fuels the development of those next generation flywheels and smart trainers, leading to ever more realistic experiences. What’s next? Watch this space.