Step 1. Find EXACTLY where it is coming from. Baby powder will be your friend. It will stick to the oil.
When you say oil vent, what are you referring to? The breather is pretty well hidden from view. You might have the older style breather, which absolutely could be your issue. What year R? (Somebody please remind me when the part number changed. <= me)
Some oil leak areas from TLs.
Side cover (it is plastic and can warp. The 97s had an additional design flaw, but not relevant here.)
Old style crankcase breather (Again, 97s had a different trouble here too. Again not your concern.)
Give us a little more info.