Originally Posted by John long
I agree with you Safe. Mine becomes smooth at about 400 to 500 also. If the 2 inch pulley will make it run smooth at setting 4 the machine will be running as if it is on 2. (half speed).
Where will you (or where did you) source the 50mm pulley? IIRC, these aren't your regular hardware store pulleys because of the unusual shaft diameter.