2 stroke scooter problem?

[clive]

i have a 2 stroke scooter l have it since 2002. the problem is now it runs 1/4 of it`s original speed. it is very slow. sometimes it won`t move even in WOT, and much worst, it dies. i`ve cleaned the air filter, and the carburetor. could it be that the clutch or the stator need service?any help?
yes it revs up but when i take it to the road it feels like i`m just walking because it is too slow. and there`s oil coming out it the tail pipe.