How Relevant is Flywheel Weight for Indoor Bikes

It is common knowledge that indoor cycling bikes have different flywheel weights and sizes. Some spin bikes like Stages SC3 have flywheels that weigh as high as 45 pounds or some spin bikes like Keiser M3i that come with flywheel as low as 8 pounds. One of the most frequently asked questions concerning indoor cycling bikes is the flywheel weight and its relevance to cycle functionality. Does the flywheel weight impact the bike’s functionality? Is a bigger flywheel weight better than a smaller one? Well, let’s find out!

Bike Flywheel ComparisonHeavy Weight FlywheelLight Weight Flywheel
ResistanceMore resistanceLess resistance
MomentumMore momentumLess momentum
MaintenanceMore bearing maintenanceLess bearing maintenance
PortabilityMore difficult to transportLess difficult to transport
ImpactHas more impact on the bodyHas less impact on the body
SuggestionThose with bad knee or senior users should avoid heavy flywheelThose with bad knees or senior users should consider light flywheel

How does spin bike flywheel Work?

how does spin bike flywheel works

Before we provide answers to these all-important questions, it is critical to shed some light on the workings of the flywheel. This will help you grasp its relevance and provide insight into its impact on your ride. That said, when you engage the pedals during a workout session, the sprockets and the drive system facilitate the rotation of the flywheel.

Most outdoor bikes feature a configuration where the drive system facilitates the movement of the rear wheel. However, indoor bikes have a different configuration where the drive system controls the movement of a front-mounted flywheel.

How Does Flywheel Weight Impact a Ride?

How bike Flywheel Weight Impact exercise

In truth, a flywheel’s position and weight affect the performance and stability of an indoor bike. The more you pedal, the more the flywheel generates momentum, and the weight determines the duration of the momentum.

In cases where a flywheel of spin bike runs off a resistance magnets or pads, the momentum will be significantly limited. And if the weight of the flywheel is on the light side, the rider can effortlessly bring the bike to a stop. However, the momentum will be shortened compared to when resistance is at play.

Is a Bigger Flywheel Better Than a Smaller One?

is bigger spin bike flywheel better

According to popular opinion, a bigger flywheel is better than a smaller one. But how true is this notion? If we are to consider the law of physics where sufficient energy is required to get a heavy object in motion as opposed to a lighter one, we’d say that you only need to expend more energy to get the flywheel in motion with the first pedal stroke. But the moment the flywheel is in motion, speed and momentum are all that matter. So going by this, the weight or size of a flywheel has little impact on its efficiency. It all boils down to its momentum and speed. The only case where flywheel weight plays a role is in generating resistance.

Some heavier flywheels may produce stronger resistance that mimics the realistic feel of an outdoor hill climbing or biking experience. But this depends on the resistance mechanism being used and the brand of the bike. In a nutshell, heavier flywheels demand more energy to get started, and they may produce a stronger resistance. However, if you have no need for a bike with a difficult starting point or an unusually strong resistance, lighter flywheels are just as good. Lighter flywheels are just as efficient as their heavier counterparts!

Does Spin Bike Flywheel Weight Affect Calorie Burn?

indoor Bike Flywheel Weight and Calorie Burn

You may assume that since heavier flywheels demand significant energy to get moving, there will be greater calorie burn. But this isn’t the case, as exercises tend to expend more energy when working out at set speed with applied resistance. The higher the resistance being generated, the more calories you will burn.

But bear in mind that there are different spin bike resistance types, such as contact and magnetic resistance. So if a flywheel is on the heavy side, but its resistance mechanism isn’t up to par, you may not burn as many calories as a lighter flywheel with a quality resistance mechanism!

In summary, if you are concerned about intensity, then flywheel weight doesn’t matter too much, but the resistance mechanism does. But if you are looking to simulate an outdoor ride or want enhanced stability, then a bigger flywheel may satisfy your needs. Finally, if you want a bike that is easy to start, then consider one with a light flywheel!

Robbie Ferri
Robbie Ferri

Robbie Ferri from “Riding with Robbie” has been cycling for almost ten years. In that time, he has broken World Records, Bikepacked all over the World, and also raced ultra distance at a top-level. Robbie picked up a bike and started cycling when he was about 25 years old and said it was the best thing he ever did. The experiences and the fun he’s had have given him a huge passion for helping inspire others to ride further, farther, and get fitter.