When I saw the dust on the intake, and saw that the donut was dry, I assumed that dust either got past the donut, which is not pushed up against the airbox very well, or got through the donut which was not lubed.

But looking at this photo again, I see some dust on the air filter holder, between the screen and the donut. It seems to me that any dust that came in through or past the donut would have then proceeded on into the engine, and therefore would NOT have gone against the air flow and settled on the inside of the holder.

Therefore I wonder if the stock filter, with the stock lube on it, wasn’t sealed up against the holder or didn’t stop the dust from coming through it.

In all of my rides since then, I have been in front and so there has not been any opportunity to find out if it is still letting dust in.

Your thoughts?