[Gelbster]

As you probably realize, the chattering is just a symptom of uncorrected imbalance. There is no harmonic balancer on the front of the crankshaft so depending on the severity of the imbalance, your engine is experience gross,momentary overloading of various bearings and sundry other items.
The best remedy would be to get a good,used DMF balanced (with the clutch assy)and fit it.
You may be more interested in refitting the DMF if you consider the potential problems that will emerge from ignoring it.
There is lots in Search on this subject.