Ive been playing toribash for a while yet theres one thing ive tried to do that doesnt work...doing a followup dismemberment. If i knockoff uke's arm i cant seem to get enough momentum to dismember anything else, (except a few acceptions) if i helps ill post one of my replays....

Well, the only advice i can give you is this:
use all of your body parts, and the ground helps a lot too.

One thing to say. Lower dismemberment hold and try it again. (Don't try too hard or you'll dismember yourself!)

Ignore what he said. Try to learn how your torso joints move. The chest is a really powerful joint if used correctly. Also, moving asymmetrical increases the power of your moves.