I am trying to help a buddy out with his XR100 and the clutch will not disengauge. I have verified that all the parts from the basket outward are all there and assembled as the diagrams show. However, the pin will not push in to release the plates. Any ideas? Also, any description as to how the plates are actually supposed to be release by the pin being pressed would be greatly appreciated. I understand the concept but can't seem to Literally see how it works.