Got the diagnosis from the BMW doctor the other day. He said "You got a sick puppy there". The right cylinder was "defective". Possibly out of round or the entire bore was off. I guess sombody fell asleep at the switch on the assembly line. So much for quality control. It was decided to just change out the right cylinder and piston by the BMW rep.. I argued my case for a new engine. According to rep, there are no 05 engines left as spares. When they determine the new model engines seem to be O.K., they use the spare inventory in the bikes they are producing(or something to that effect). My bike was only 8 months old at the time of the incident. I spoke with the dealer and told him that I wanted both cylinders and pistons renewed for continuity. It's a new bike and I don't want 16,000 miles on the left side and be breaking in the right side. This would also throw the maintenance schedule off. He agreed with me and it was decided to change both cylinders and pistons. The oil and filter were examined for metal and none was found. So, hopefully that won't be a problem. I got the bike back yesterday and so far, it's running great. So much so that I am now convinced that the knocking noise was always there. When I purchased the bike and was "riding off" on it, as I let the clutch out and loaded the engine, there was a knock. I asked the dealer who was "waving me off" what's that? Is that normal? He said "That's no problem". Some of these bikes are a little louder than others.???? The sound doesn't exist now. It has a sound which I now preceive as normal. The "traditional" sound is gone. It stands to reason to me that if one of the cylinders was a problem, I may have been correctly hearing the symtoms of what turned into a major headache for me. When it finally "blew", The knocking noise now seemed to be an amplified version of what I have always heard from square one. Anyway, I'm not a "Happy Camper" that this all happened in the first place. I have a different perception of BMW now. I had to pressure them and raise hell a couple of times to get things done to my satisfaction, but in the end, they came through(I hope). When I first talked to the BMW rep (before we got to the point that we decided we didn't like eachother any more), he was on his cell phone from Colorado. He told me he was enroute to check on "another" 05 with a similar problem. Well, I don't want to sound like a cronic crybaby. I truly like the bike and hope it is "well". My last trip was truly great and I met some incredible people and had a wonderful time. Breaking down and mechanical screw ups are "Part of the Joy of motorcycling". Let's face it, just to bring ya back to reality, if it gets to heavy for ya to bear, you can alway just WALK. All the best, Smitty