Seems kinda like the old bicycle generators were for bikes. Once battery technology got decent, the generators were obsoleted. But for sleds, I could totally see this, given the power needed to run heated grips and the OEM lights.
The idea of lights on a kart sound fun, but unless the races were 24 hour or endurance type, battery power would seem to make the most sense. A good light that could handle the vibration, etc, would be key though.
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