I just did the valves on mine. I found it to be somewhat huge at first even though I've done valves before on smaller easier engines. Could do it again in half the time now I suppose but still think it's a big chore. I spread it over several days since I could use the car while the scoot was apart.
I'd figure on 6 to 8 hours of pretty constant work, if not a little more. You'll want very good lighting to see what you're doing in the head. Also a cinch strap or some way to compress the rear suspension. I found the valve cover would NOT come out through the frame unless that was done. Thanks to Zombie here for the advice on that. Finding just the right way to put the strap around the frame/through the wheel was an adventure in itself.
Other tools: feeler gauges of the correct thickness. A small valve adjustment tool -- I made one by cutting up parts of the inside of a ballpoint pen, though the Kymco tool would've been a lot easier. Also the 9mm Kymco wrench for the lock nuts would've been very nice ... I had to buy a 9mm offset end wrench and wound up having to grind it very thin at the neck. Lucky I had a bench grinder.
Other hard parts were getting the decorative plastic panels off the side of the floorboard hump. They're a real bugger as others will attest. You must pry upwards really firmly with your fingertips and palms to get the first 3 bottom tabs to start to come out. Plan on sore fingers after that part.
I'm going to be real busy this week or I'd offer to walk you through it in more detail.
If you've never adjusted valves before, I think I'd let the dealer do it, though.
