sounds like you are having the exact same problems as me. The leak is probably from you your exhaust cause you coated everything with oil when you did your rebuild and now everything is comming out the exhaust. I changed my y-pipe gasket and that seamed to solve that problem. As for the highier idle.
did you try riding up a trail at all cause i noticed that when i went highier in elevation it went away 1500 feet was what you were describing and 5000 feet it was gone acted like a normal sled. Winterbrew sugested turning the fuel screws 1/2 a turn. I haven't tried it yet but that might be a good place to start. Let me know what happens cause i want to know as well so i can get my sled running well.
