1989 2 stroke ex go revs high moves slow.

[Grizzlyrider]

I recently purchased a 1989 2 stroke ez go for dirt cheap. It's a fairly decent cart for the price, but has one issue that I am at this time struggling with. When pressing the gas it moves right away with no hesitation however it moves slow. The engine revs up as it should but the speed only ever so slightly increases. Under load it never does seem to get much more than walking speed. I jacked it up and pulled the seat, the clutchs seem to work but with little to no knowledge of golf carts, they seem slow to move as well. Any help would be appreciated. Thanks.