Because you also asked… and asked
Okay, you’ve seen how to shift gears on an old-skool Vespa. Some of you wonder how a modern twist ‘n’ go scooter shifts gears. Well, it doesn’t. It has a continuously-variable transmission. Here’s how a CVT works:
The pulleys, called variators, change size steplessly, allowing them to find the “gear” ratio best suited to speed, engine power, load, etc. An amazingly elegant device. Yes, this video shows a CVT in a Polaris snowmobile, but the principle is the same, whether the vehicle is a scooter, or a Nissan Maxima.