Brief background summary..... Bought the bike yesterday, 2014 with Zero miles. I rode it home yesterday and since I was 40 miles from the dealer I started the first part of the trip on the service road and side streets. Not knowing how much break in was required on the Honda engines I took it easy on the side streets taking it through the gears up to around 6-7k and then lettting off the throttle and draw a vacuum on the cylinders in hopes to aid in proper seating of the rings. I could only do this for about 8-10 miles or so until it was on the highway. Rode the rest of the way home about 60-75 changing between 4th-6th frequently and no more than 1/2-3/4 throttle. I put 40 miles on it by the time i pulled in the driveway, parked and admired it for a while. Today I hopped on and put about 105 miles on her and say 8k a couple times under moderate throttle, all was well and rode great. I wear a helmet so I could not notice the noise until I made it home. When I got home I parked it went in and ate dinner with the family, I came out about half an hour later and went to move it into the shop. I had no helmet on and I fired her up, coolant temp was still about 160. I blipped the throttle a couple of times and pulled her in the shop. What caught my attention was when I blipped to 4-5K, upon the deceleration of rpms I heard a tinny sounding thunk. It sounds like its in the exhaust somewhere. I did it a few more times and it did it every time. Any thought on what it would be making the noise, whatever it is it resonates out towards the exhaust. The best way I could describe would be a small hammer dropped from about 4" on to a piece of 1/4" plate steel. So it has me a little worried, It appears the bike has a catalytic converter so I wonder if something in there or a valve could be the culprit. Other than that I noticed no weird performance today when I was out and about. TIA ETA: DO THE 8TH GENS HAVE A FLAPPER IN THE INTAKE, COULD IT BE THIS VALVE CLOSING UPON DECELERATION OF RPM'S?