All these bikes whine because of straight cut gears. The entire edge of each gear contacting with each other as they mesh is what you hear.
Look on the bright side, Its annoying to hear on these ventures (Untill I got some Barons pipes ) but I had a BMW pull up and park near me once, and the whine was 10x worse.
There is a way Yamaha could reduce the noise by adding slant-cut gears so the mesh with teeth rolling into each other like:
//////////\\\\\\\\\\\\
Then the noise is GREATLY reduced. However, this causes the gears to want to slide up on and down on the shaft -- hence they go with Straight cut ||||||||||||||||.
Idealistically they'd create V shaped gears that mesh >>>>>>>
At least, that's how it was all explained to me when I asked my gear-head riding bud. (I asked why they don't have V gears)