You Know....I LOVE my ride....I have had many bikes over the years and could barley afford to ride them, now I have the iron horse I thought I would never have and can afford it...I love my ride but have the rattle at 2200 RPM, I asked the dealer if I could pay them to get rid of it...PAY them...and they said, no...it is the nature of the beast. Hmmm.
Still love the bike, best bike I have had so far...TIC...TIC...
Noise issues can be very tough, since they are subjective at best and open to interpretation. Five different people on this site could listen to a particular engine and probably come away with five different opinions of what the cause is and whether or not it was acceptable. So far one dealership has told you "it's the nature of the beast" and won't attempt to fix it. I suggest you get another opinion from another dealership, and then call H-D and ask for an appointment with a service rep. The rep may not be any better than the typical dealership person when it comes to tech ability or honesty, but it's necessary to give them as much rope as it takes. Get all these opinions in writing and file them away with the rest of your documentation for the bike. After they all tell you there is nothing wrong with the bike, ride it and don't worry about it. If it fails later, take your documentation and do what you have to do.
Funny thing about the quick answers from dealerships and from H-D. Normal, they all do that, nature of the beast, etc., if it's true then every single one that they roll out should do the same thing. We've already heard from people who had dealers fire up another 110 right beside theirs and compare, and found that the other bike didn't make the same noise. We've also heard from some who took it upon themselves to tear into their engines, or somehow convinced their dealers to do so, and look for the problem. Tapered cylinders, bad lifters, etc. have been found by some, and of course back in the beginning there were plenty of valve spring retainers hitting rocker boxes (another "normal" condition until they were forced to tear some down and saw the witness marks).
I don't know of any foolproof answer to the lack of response from the dealers and from H-D. Sometimes polite but persistent works with H-D, sometimes it takes getting a little nasty, and sometimes nothing helps. When you buy a product from a company that doesn't care about customer service and has a history of blowing off customers with legitimate issues, I don't know that there is an easy answer. When enough of us refuse to buy another one perhaps things will change.
Jerry