I recently changed the air filter on my 05 wee and when I pulled the old air filter off I noticed about 1/4 cup of what looked like oil in the "pan" the filter sits in. Smelled a little like gas. I have owned the bike for 9 months and just got around to checking out the air filter, (dealer said they changed it), they didn't. It was probably 2 years old, very dirty. The bike has 45K miles on it. Is this normal to find? What is that stuff in the bottom and should I be concerned? It was a stock filter, not a K & N, that I took out so I don't think the oil is from that. Any ideas?