first thing i would do is pull the spark plug, and make sure it is the right plug for your modle moped, and while the plug is out look at it, if you don't know how to read your plugs, take a look at the lower half of this page. http://www.amiles.com.au/rmr/SparkPlugReading.htm
or this one.
http://www.nh-scooters.com/article/articleview/55/1/2/
doing a basic tune up can help reduce your fuel consumption, and improve proformance alot.
a tune up would consist of checking over the entire bike, makeing sure everything moves as it should, cables, wheels, brakes, no binding, grinding or exsesive wear, also oiling cables, and inflating tires, basicly look at each part, poke it with your finger, and ask your self if it looks like it's doing it's job right.
then move on to the engine, starting with where the air goes in thru the air filter, clean the filter, look for leaks and cracks, make sure your choke works right, if it doesn't start, run, and idle right, fix it! then check the other side of the engine, were the exaust comes out, how dirty is your muffler? clean it, some like burning it out, I like useing a soft mallet to shake stuff loose, then rinse it out with paint thiner, or kerosen.
if you have the knolage and specs, checking points and timing can be a great idea, otherwise there is no time like the present to learn, or do like some people do, and take it to a shop, of course most people can safly assume that their timing is correct, unless they go thru everything else I said, and still have problems.