The i3s technology is a patented stop-start system developed by Hero MotoCorp to improve the mileage of its bikes under the Indian riding conditions. When you stop in traffic for more than 10 seconds in neutral gear, the bike will automatically turn off. When you engage the clutch, the bike will start again. This technology helps keep fuel consumption as low as possible. The i3s system is available in Hero bikes. There are several videos available on YouTube that explain how the i3s system works in Hero bikes.