We just bought a 2007 for my wife, and it has been sitting for three years. It, too, has the same issue. When I pulled the airfilter, runny oil poured out of the frame. By the next day, most of the spill had evaporated. I suspect a bad petcock allowing gas to pour into the crankcase and raise the oil level high enough to be sucked through the breather tubes, thence to the airbox/frame. Prolly need to replace the diaphragm and clean everything within an inch of itsĀ“life. Drain the fouled oil and replace the filter. Wotta mess....