Revtech 110 blowing oil out the air filter, I sent my bike in for its first service (1000 Miles) and since the service the motor keeps spewing oil out the air filter... oil level reduced as i thought maybe over filled. I removed all the oil and filled 2.5 Liters (which is very little, I think) ... In town the motor is fine and dose not leak at all, but if I go for a run on the open road the oil comes out the filter. My mechanic did a compression test and says all is well. Can anyone help...

Oil coming out of the breather is normal on these engines by the way of design, with basically no way to stop it. There is about 1/2 qt of oil in the bottom end of an engine, as the pistons travel downwards, the air that is under them is being pressurized and is vented out of the engine by a rotary breather valve in the case. The air picks up a small amount of oil from the bottom end as it leaves, then the air/oil mist is vented either into the air cleaner (EPA Regulations) or best if vented to the atmosphere. When it's vented into the air cleaner, some if it recirculates into the engine and out the exhaust, the rest saturates the air filter and then eventually gets blown all over the side of the bike. The best way to vent it, is to route a hose from the breather system down to the frame between the engine and trans, run it under the bike on the right side, point the hose down to the ground and zip tie it in place...Be sure to point the end of the hose down & away from the tire.
If your breather bolts start to leak oil...remove them, and use brake cleaner to completely remove all oil from them, the washers, brackets and threads in the head. Use liquid teflon thread sealant on the bolt threads, and a light film of black rtv on the faces of all the washers and brackets, install everything, let sit for 24 hours, then ride.......if done properly and rtv is CURED, it won't leak...
Also note that most HD's with the oil tank mounted under the seat and are left sitting for a couple months will PUKE oil from the breather, this is due to the gravity....the oil will slowly seep through the oil pump and collect in the bottom of the crankcase and get blown out the breather when the bike is started ...

Good luck...i hope this helps

NEW REVTECH 110 engine oil 250 is this too high?What is the normal temperature

As it is under warranty, take it back to the supplier and let them have the problem. It may be expensive, or just a vapour lock occuring.
I have found an answer but I can't download it due to a browser problem. Here is the location and I hope you can:- http://answers.yahoo.com/question/index?qid=20090802132413AAyP4I3
My 1976 XLCK 1000 Iron Head used to do that. Give it some work and oily boot time. That was caused by the lower breather pipe behind the dynamo, it was blocked and oil vapour jammed up the sump. I think it wanted to be a two stroke!
Hope that helps and ride safe.
Loud pipes save lives.