The fuel injection is a nice factor, though I also got it because it's a 4 stroke and doesn't have the smelly oil factor. One thing though, is that I've noted a lot of people say they're getting pretty close to what I get in terms of mileage, so I find that a bit surprising considing mine is fuel injected.
On the other hand, I've noticed the C3 is kind of...fatter than your average scooter, and has a bit thicker tires too, so I'm willing to wager that some of the increased efficiency of the Fuel injection might be offset by increased weight. (It certainly isn't being offset by increased power, I can tell you that for sure)
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