Looks like you have seepage between the cylinder head cover and the cylinder head of the rear cylinder, or maybe both cylinders (the 2nd picture might be the front but not sure). You can start off by simply tightening all the cover screws (there is a bunch of them, a dozen or more for each cover). Then clean off as much oil residue as you can and see if it comes back. It might take a few cleanings and long rides to be sure it is corrected. I have not removed any cylinder head covers on my Liner yet but I think you can get an Allen wrench on all of them screws after you lift off the gas tank and remove the air filter box.
Good luck, hope this does the trick.
Last edited by stratowart; 12-10-2012 at 11:54 PM.