I've worn the search button out looking for possible cause of the vibration on my new to me 2011 SG. After going down the list and checking it twice, on a whim I removed the Amazon crash bar that I'd put on it. Boom no more vibration. It may be because Aluminum doesn't dampen vibration like steel, I don't know. Just wanted to throw it out there. Great group here, I believe I could dang near build a bike on the search button alone!

 

My 08 road king had a mustache bar on it when I brought it. No vibration. I added the long mounts with mini footboards and boom vibration lol...as long as keep a toe on at least one of them the vibration is gone. It's the stock steel bar but adding the extra weight or the location of the added weight just hits the wrong harmonics or something.

 

Dude, its a Harley, and even with loctite on every bolt and nut, someone is going to be rattled loose give enough time.

As for items added on the bike, remember above, and on some items, you have to add in a dampener to the bolting system, so you don't at least get a rattle there to begin with. And keep the above in mind with after market devices, since some are not built for the HD vibrations to begin with, and even if you dampen the device to the bike when installed, its internal parts may be worse than a babies rattle from the onset as well.

To add, HD has been pretty much steel and iron from the start, why they weigh so much. So forgo trying to installed lightened parts, since the few ounces saving here and there, is not going to off set the dam near 1K weight of the rest of the stock parts instead.

 

I definitely wasn't trying to add lightened parts intentionally. I'm guilty of adding cheap parts, and it bit me.