Well Greg, I did the filter leaning and cleaning under the sprocket cover when I changed the sprocket. Used carb cleaner, rags, a nylon bristle brush, etc. Got it good and clean too.
FJ, I doubt it's the chain lube, but I'll pull the cover and check...
I remember someone having a leak from a seal around the sprocket shaft or something that would drip down and onto the filter, as if it had come FROM the filter, but actually higher. I need to lift it WAY up and get a good light under there and see.
