One thing you may not be aware of is that the RevTech Gen III engines, both 110, and 4X4 100 don't use a breather gear like old evo engines. The RevTech is a bit of a hybrid in some manors. the engine even though it is a "dry sump" style engine can hold more oil
in the crankcase than a standard Harley. Now at the bottom of the sump plate, there are two set screws facing outward. They are directly connected to the oil
sump and system. You may pull those and find a fair amount of oil
. Now again with out a breather, and over time engines can leak past the check ball in the oil pump. This is not anything to really worry about, but I will tell you something else. Call the guys at Custom Chrome and ask them about the "oil system performace update" This is a "Free" update they provide. It alters the oil system in a way that further reduces the oil in the crankcase. The plus of this is reduced engine temp, and a slight increase in HP. Not a bad gig, and I have peformed this myself for people, and one it's simple, and two it fricken works great. I have seen a reduction in oil temp in the oil tank up to yes, 100 deg, plus on my dyno Jet 150 I have also seen an increase of 7 HP. Yep no other changes. I hope the explains there is a drain on the engine case, and two, take my advice and perform the update, you will go away smilin. Good luck, and stay in the wind!