Now there’s a revolutionary technology that allows you to adjust your bike’s ability to conquer almost any terrain without using real gears. It’s called the Nuvinci Continuously Variable Planetary Drive. And yes, that’s a mouthful. But it means that you can go from what traditionally would be a low gear to a high gear without having to move the chain from one gear to another. That means no jarring when you shift gears. It means no loss of power as you shift gears. It means no gears slipping. And it means no problems if you have to come to a halt at the bottom of a hill, or find you don’t have the speed to shift into a lower gear to another.
The engineering behind the Nuvinci, by Fallbrook Technologies, seems a little like black magic. Instead of having gears inside the hub you have a series of rotating balls laid out around a center axle. Two rings circle the balls. As you twist the handlebar mounted shifter, a cable is either pulled or released, and that changes the angle of the wheels in relation to the rotating balls, that in turn changes the output to your rear wheel.
Because there are no gears, you might wonder how the entire system maintains internal traction so the balls and the ring don’t simply slip. The answer is the secret sauce. A fluid I don’t even pretend to understand. But it works. If a picture is worth a thousand words, I suggest you checkout the video below to give you a much clearer idea of how this all works.
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