whistle on my bike

dug my t80 out  from under its winter  blankets this week as the weather decided to be more suited to riding a bike than driving a car
on its first run there was a sound not unlike a whistle coming from the front section of the bike checked the wheel tight , wheel spins freely with not sounds checked the exhaust nuts both tight
all I can think of is wind noise, as it does not alter with the bikes speed and  is not do it all the time only over 30 mph, will make the noise as I accelerate and on deceleration
have had the plastics off  over the winter
will try it with out the plastics after the snow

Yes, here it comes again, "The Beast" MK 2. Nice and sunny here today so i was out on my Townmate, loved it.