Hello: If it is a hydraulic clutch then it isn't a linkage problem, thats for sure. Wonder if they put the clutch disk in backwards. In most cases this is not possible, but if it can be put in backwards then the hub of the clutch that has the springs will not work and act like a springless center hub. Possibly grease on the surfaces, sometimes that makes them shudder. I don't know what else it might be without a little more info.
Good luck
Darryl.
Monday, January 16th, 2006 AT 9:12 PM