Hi. I have a DL-50 in an Extra 330L that as of today has 21 flights on it. From day one, the engine has emitted a fine black mist on the cowl, LG and wing LE just downwind of the stock muffler. It runs fine to me, but it is my first gasser. A couple swipes of the towel with Windex, and it is gone, so I have not given it too much concern. Any tips on what the cause is...do I need to adjust the engine or is it just normal? Thanks. Jon