Bodywork vents tested

[Bluebottle]

I ran some aerodynamic tests to determine what that little vent in the bodywork just under the front of the seat actually does on Burgmans etc.
The question has popped up in various threads and there have been a couple of different theories put forward.

I have always thought that it must vent outwards, because it is in a low pressure area.
The test showed exactly that:
When you are on the move there is a flow of air from inside the bodywork out through the vent and forward over the tunnel.

Why?
I assume that without it there would be stagnant air under the seat around the throttle body and engine that would get hot.
The vent gives air rammed in at the front somewhere to exit and that creates a managed flow in the upper areas of the main bodywork.
I suspect it also helps balance the pressure behind the fairing so that the rider isn't sat in a vortex from hell, the flow around the bodywork is improved and the flow throught he radiator and bodywork is increased.

So what?
Well if your a tinkerer this might be useful to know.
Some mechanics seem to have been trying to use this vent to improve the flow of cooling air into the CVT on the AN400. The trouble is that this vent is blowing - not sucking so it will stop the CVT drawing air in or worse, draw dirty air backwards through the system bypassing the filter.
This fits my second theory: about why the CVT filter is cleaner when you snorkel air from this vent on the 400 Burger. The filter is clean because there is no air going through it - not because it is finding cleaner air.

The CVT snorkel on late models should open into the tunnelin high pressure air, not at the vent.

I haven't done a full study of the flows and pressures or anything, I only had time to look at this one little area but if I do any more I will post it.

[Data]

That's interesting Bluebottle. I'll follow my cvt air induction tube first chance I get to see where it goes. Judging by the state of the cvt air filter when I cleaned it, it probably doesn't go far. My filter had dead flies (sorry, they could be relatives Bluebottle), bits of straw and other debris stuck to the outside of the sponge. Nice research though. Thanks for the info.