Had a little "fading" in power recently that seemed similar to vapor cannister sludge ingestion experienced in other vehicles. So I went on a hunt for this thing. Wound up removing all the Kymco Tupperware from the back to the leg shield. Turns out the real culprit seemed to be the little vacuum controlled "switch" that vents the fuel tank fumes to the cannister. It seemed sticky so I removed it and re-plumbed the works so the vent line is open to the tail cone of the machine. I put a small fuel filter on the end of the now vent line to keep crud from the inside of the vent line. The cannister is as far aft as you can get on the scooter and still be inside the plastic "body". It is behind the battery box. The vacuum switch under the floor board, left side outside of the frame tube, just inside the CVT cooling intake. Test ride showed no "fading" in the engine output but hey! It was always intermittent anyway.
Karl