Hearing something on the bike can be really deceptive too. I had this rattle/whine that I could not for the life of me pin down. Sounded like the front end. After a season of dealing with this and the dealer tech saying he had no idea either I finally figured out it was my tank. My shade tree mount I made for the tank wasn't holding it down tight enough.

2008 Speedy, AI removed, DIY airbox destruction with K&N filters, spectres, re-jetted and "custom" rattle can paint job.