I ride a 2003 Roadking FLHPI. Recently while riding I started hearing a whining/squealing noise coming from the engine. I narrowed it down to when I shift to 3rd and 4th gears is when it makes the noise. The noise stays there until I shift off of them. When it's in 1st, 2nd or 5th gears it sounds fine. What could it be? Thanks for any help.