Chirping & Tweeting at low openings?

Ok guys, what is that noise?

My SD didn't do it, but the SDR sings like a canary.

What's the score?

The best I can figure is that it is the sound of the air getting around the secondaries while the are closed. At low throttle primary butterfly openings try to pull air around the secondaries and it produces the chirps and tweets that you here when you are trying to be a good citizen. They were there with the air box but muffled.
Someone please correct me if I'm wrong.

My bet is that the new 'flies that Aaron has made should be free flowing enough to put an end to the sounds of "Disney birds" flying around our heads while still keeping the worst of the volume down and keeping the beneficial airflow affects.

I love the overall differences the box has made. The chirps and tweets are a small price to pay for the gains but if the new 'flies can help well....

There are all sorts of odd noises that come with the motobox, they where there all along but without the muffler of a stock airbox you can hear them.

Nothing to worrie about

I don't mind them at all. I just wondered what they were.

yeah def the moto box!

She is singing her love to you Dutch, its all good

Put the new flies on today and the bird noises have flown the coup. A little more rasp from the MH box. Humidex is at 40'C so will have to wait and see about power characteristics.

I dont get that noise, maybe its cos I wear ear plugs, either that or im due a refund

I guess you're one of the lucky ones. Mine would whistle on start-up and singing like a bird at small, steady throttle openings, like putting through town. All seems well now.

its a bit of an aside but was the k&n filter that comes with the motobos pre oiled ? I get the whistle at tickover with the motobox as well.