sounds like an automatic pressure relief switch for head pressure...maybe not, my UC does the same thing and for sure sounds like pressure being released.

 

I got an 06 with SE air cleaner and it does the same thing. More of a whistle. Not every time. Never thought anything of it. If I worried about every sound that comes from a Harley I would kill myself! [sm=alcoholic.gif]

 

Yeah! Too many strange noises to worry about

 

My RKC does it too.... A low whistle right about the time the engine comes to a stop...not every time...I'd guess about every 3rd or 4th timeI shut it down....Is this happing on fuelinjected bikes only??? Maybe fuel pressure bleeding off???

 

They all do it, only with stock air filter its muffled.

 

I think it's the little squirrels running in the cage catching their breath after a long hard ride.....just my opinion....Bldr