It could be that the teeth on the end of the push rod axle aren't/weren't engaged properly with the teeth on the pull rod and are either slipping or not moving the push rod at all? Alternatively, if the teeth on the pull rod (sticking out the clutch assembly) are facing the wrong way (rearwards) on assembly the clutch push rod won't move and the teeth on the pull rod can get mashed up like this...



Either way, if you are sure the external parts are all in order (cable, freeplay, lever, punch marks etc.) then you're going to have to resign yourself to taking the cover off and inspecting.

The interesting thing is it happened after an oil change. What oil did you put in? It is quite possible that the oil used could have swelled the friction plates locking everything up - the "wrong" oil doesn't always result in clutch slip; a common misconception. I've seen/heard of several sets of clutch plates ruined by the use of "Energy Conserving" oils, just ask SteveD! BTW - contrary to popular belief, the wrong oil doesn't mean synthetic, nothing to do with that, it's stuff labelled "Energy Conserving" (usually, but not exclusively car oils) that are the problem due to the complex additives which reduce friction and cause swelling in multiplate wet clutches; it just happens to only come in synthetic form. It should never go anywhere near a wet clutch.

Use only JASO MA certified motorcycle oils suitable for wet clutches, which can be mineral, semi or fully synthetic.

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