ok, the 5 speed? if so, the shift forks can be stuck, or rusted in place and they wont slide. Make sure its not the linkage itself binding up- trash or piece of the old drive belt stuck up there-, if not, your probably looking at an internal transmission problem.
I looked around a little, those are what are called CVT, constant variable transmission. if your linkage or directional is moving ok, you probably do have something hung up on the inside. Hard to give you any advice on that via web
