Hey guys, new to the forum here, first post. My wifes 06 heritage has this strange whirring noise from the front cylinder. At idle everything sounds normal, when you steadily roll the throttle back off idle you can hear it (even my wife can hear it!) Bike has 11,800 miles, mobil 1 syn. hasn't had any mx done on her lately that might be the cause of this noise, any ideas. Just seems to be from the front cylinder. Actually thought it was her windshield causing the noise but that wasn't it. Any ideas??