the dealer is likely just putting the needle float back into place or its had time to settle into place after being shut off when he checks it out... keep in mind, he is checking in the parking lot, not at full speed for 20 minutes. My dealer had never heard of the problem before, its a rare issue. But the fix is simple. You can do it yourself... its the screws on top of your carb, you can reach them through the plastic carb door under your seat... those screws open up your carburetor and the needle float is dead center, and it just twists into place..... though it is a tight fit with the seat pan in place. I would at least check to see if the needle float is moving out of place... if its in place, under the tabs, when it won't start then it's something else. One thing to keep in mind with scooters and motorcycles... no matter how reliable they are, they do need work from time to time... it's a good idea to get comfortable working on your scooter. Sometimes, just knowing a little bit is all you need to get it home after it breaks down. It also helps keep the costs down when the warranty is gone. Good luck.