I have a 92 fxr with oil weeping from breather also oil in tank becomes aerated after only a few minutes. Any help appreciated.

SOURCE: i have a 1990 harley

This is a common problem with the older bikes. The reason is the position of the oil tank and the type of oil pump the engine is equipped with. With the tank being higher than the engine, oil will seep past the check ball in the oil pump and into the engine. When you fire the engine up, the oil pump cannot pump the excess oil back into the tank quickly enough and some gets blown out of the crankcase vent. If you allow the bike to sit for extended periods of time, this problem is worse. It's commonly called "oil sumping" around here. When you hear an old Shovelhead rider talking about his bike "puking", that's what he's talking about. I've seen those bikes puke nearly a quart of oil after sitting a few months. I've seen Ironhead Sportsters completely drain the oil tank into the engine. This is normal to a degree but if it gets too bad, you can "reseat" the check ball by removing the plug above the check ball on the oil pump and use a small hammer and punch to gently tap the ball into the seat in the pump. Then, remove the old ball and drop in a new one.

Good Luck
Steve

SOURCE: what could cause excessive oil pressure in the oil

Check your crankcase breather hose. On the '88 model, it originally came from way down low behing the oil pump up to the backside of the air filter plate. If the bike was purchased used, the original owner may have rerouted the hose in order to avoid oil getting into the air filter. Find the crankcase breather hose and check to see if it has been plugged by something or has become crimped.

I'm confused by the term "breather valve". I don't know of a breather valve on the engine. If you mean the "breather gear" in the cam chest, this is good as the originals were made of plastic. These would break a tooth off the gear and quit turning. Usually the broken tooth would lock up the oil pump and indicate a problem in the area. However I have seen on occasions that the oil pump was not locked up by the broken tooth and the engine would build up too much pressure inside. I've seen the pushrod tubes start to leak because of this. If I have misunderstood and you have not pulled the "nosecone" on your engine to check the breather gear, that could be your problem as well.

But, do not pull the nose cone unless you know what you're doing. I've fixed several bikes because the owner went to check the breather gear and didn't know what all was involved in doing this. The nosecone would come off about a quarter inch and hang up, would come the rest of the way off and wouldn't go back on either. If you need specific instructions on how to take the "nosecone" off, repost and I'll tell you how to do it. You'll need a pair of tappet block pins to do the job.

Good Luck
Steve