Are you talking Barnett Kevlar clutches, or the older style?
I doubt I have had a Kevlar one in my bike.
how much stuff in the oil are we talking, I change mine quite a bit, and inspect it and would see it.
I am thinking of trying an APE one, if I can afford to ship it.
I found a lot of guys racinglet out the cluch much faster than I do, more or less dumpong it. Usually the first thing I would do on a stock bike was change the springs with stock plates, and they never seemed to shift hard nor last very long.