I need some insight here. I have an '05 1800 with 5000 miles on it. I am experiencing a pronounced, high frequency vibration, similar to that of some older inline 4 cylinder engines--like on a Kawasaki Concours, when the engine is under a load such as during acceleration while going up a hill, starting at around 60 mph. This seems to be around 2700 rpm and up. I can feel it through the grips, footpegs and seat. Bascially, throughout the bike. It's strong enough that it makes my hands start to go numb. No, I don't have the bar end weights on because I installed the Kuryakyn Erg hand grips. Does anyone have any ideas what might cause this and has anyone else experienced this same thing? I'm thinking the logical place to check is the motor mounts in case they aren't correctly torqued. But I'm no mechanic. Thanks in advance.