I am getting more than "usual" grinding when I stop to shift on my SS/18. I can push the clutch all the way in, but the belt is still turning. I have watched the idler spin even after a while of holding in the clutch. I recall seeing something about a sliding adjustment in the manual, but it looked like it was all the way "loose". I haven't changed the belt since I bought it a year ago, and I don't remember it being this way until a few months ago. Is there anything I should be looking for to make the clutch release enough to shift without grinding the transmission?