The Niro comes equipped with a parallel hybrid system, meaning the gas powered engine and electric motor run at the same time.
Many hybrids, such as the Prius, use a continuous variable transmission (CVT) that serve up good fuel economy but can result in an buzzy disconnect when accelerating; they effectively have one gear, or an infinite number of gears, depending on how you look at it. The transmission seeks to match itself perfectly to how hard the motor is working.
The Niro bucks this trend by using a dual-clutch transmission that shifts smoothly under the conditions I threw at it (heavy acceleration, climbing up a particularly steep hill). The SUV always caught up to the situation at hand, and I never felt like the transition was wonky or ill-suited to handle my driving needs.
For situations where you want a sure bout of power, you can switch to Sport mode. That will cut into the Niro's fuel efficiency, but I didn't find it necessary for basic driving.
Source : http://www.businessinsider.com/kia-niro-hybrid-review-photos-2017-7
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