Great general scooter information....

[mrbios]

http://www.jacksscootershop.com/tips.html

My favorite:

My idle is too high

    This could be due to a throttle cable that is too tight or misrouted. It could also mean you need to turn the idle screw on the carb counterclockwise ~1/4 turn. A high idle may be due to a vacuum leak. The rubber manifold between the carb and the cylinder head can crack over time. Try starting the engine and squirting some water around the carb, manifold, and vacuum hoses. If the idle decreases, you have a vacuum leak somewhere.

[mclark999]

My brother used to do this on cars but used WD40 and just looked for smoke in the exhaust.  Harder to see on a 2 stroke, but still works.  Can be a little messy.