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15-Pound, Retro-Tech Flywheel Helps You Pedal Your Bike To Tomorrow

A 22-year-old inventor combines two old technologies into a bicycle that saves energy when it brakes and can then accelerate without pedaling.

The technology of a flywheel is simple and old: Use energy to spin up a wheel very quickly. Later, you can take that spinning energy and use it for something else. But you normally think of flywheels as enormous steel monstrosities spinning in factories. But 22-year-old inventor Maxwell von Stein's new bike employs a small flywheel to boost his speed and take a load off his legs while pedaling:


When braking, the biker simply shifts gears and allows the energy to transfer from the back wheel to the flywheel (instead of transferring uselessly to the brake pads). Once the rider wants to accelerate again, he simply shifts the gear and the flywheel transfers that power back to the bike, sending the cyclist on his merry way.

The wheel weighs 15 pounds, so you certainly need the extra help it provides to keep moving. But, as the simple flywheel makes a comeback in all sorts of applications, Stein's invention shows that even the bicycle can get a boost from the the technology. Just don't reach down looking for your water bottle. You're liable to lose a finger.

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  • michael

    The problem, it seems to me, is that when you really want to stop, you primarily use your front brake.

  • GringaParnussa

    I love the comments about how it cannot work when the video clearly shows it does work and very smoothly too.  Ah, the engineers who swear that hummingbirds cannot possibly fly.

  • Shaun O'Connor

    Simplistic and as already said in previous comments, cool.

    Energy wastage is a hot topic right now.

  • 7LeagueBoots

    First off:  Cool

    Second:  Put a shell around it so no-one hurts them selves.

    Third: At the gyroscopic effect commentators - a bicycle already has 2 gyroscopes, they're called wheels.

    Fourth:  Rather than making a completely new bicycle, why not make an adapter kit for all the bicycles already out there?  You'd sell a lot more and customers wouldn't have to ditch their current ride.

  • Hpkyh47

     It would be difficult to make an adapter kit for bicycles because most frames have a single cross bar, the one in the video was conveniently split allowing the placement of the flywheel. Most bikes would require some welding and machining to the frame in order to accommodate a flywheel if it is even possible. I'm sure bicycle enthusiasts won't mind but this extra work is likely to stop the casual rider. Its a good idea though, it just seems hard to implement with most contemporary bicycle frames.

  • wickedninja600

    To anyone who says that this is not going to work because the flywheel makes a gyroscope: have you ever heard of a motorcycle? You better believe that at 90km/h the wheels of a motorcycle create a gyroscope too. The engine does as well. When riders turn, they don't fight the gyroscope, they push into the turn. Logically you would assume that if you push the right handlebar forward you will turn the handlebars left, and therefore go left; however, pushing the right handlebar forward dips the bike right, and it turns, despite the gyroscope. It works on normal bicycles too, try it next time you are out. I see no reason why the flywheel would change that.

  • Xavi Alonso

    It's a little different since the flywheel is not the wheel, or a heavy motor, in the case of this bike.  For this bike, the gyroscope is offset relatively high from the pivot axis (the point at which the wheels touch the ground).  Also, you are not thinking about ratio of the weight of the gyroscope to the weight of the bike.  In a motorcycle, the tires are relatively light compared to the rest of the bike.  Also, the gyroscopic (rotating) part of a motorcycle engine weighs much less that the rest of the engine block.

    Interesting thoughts, just a little misguided.  These projects are usually the result of an inventor with a casual understanding of physics, not an mechanical engineering design project.

  • Esteban Ventura

    really interesting concept! Also, does anyone know the same of the song in the background?

  • huggles huggles

    I meant to say...It has already been done before. This is a bit of a con and I hope the flywheel bike was NOT his exam project.

  • huggles huggles

    It has already been done before. This is a bit of a con and I hope the flywheel bike was his graduation project.

  • Swmrh911

    @ Joshywashy1111 that's the exact same thing I thought. Nice try bro, but Andy already discovered that....

  • Fill

    Lugging around the extra weight of the flywheel is going to discount any potential gains from storing the 'lost' energy from braking, imho.

  • Halosk8ingking

    how did he get the CVT (Continuously Variable Transmissions) inside that small of a place? did he make it himself? im basicly looking for a lot more info about the transmission on his bike