Even dropping it out of a plane (which would make it a LOT faster... for a brief period of time) is costly, so I'll go out on a limb and say, "no." :)
There's very little you can do to that engine to get dramatic gains out of it, and anything you CAN do will cost money -- both up-front, and in later tinkering and repairs.
The most cost-effective option is to sell the Agility, and buy a scooter with a larger engine.
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