Went on a little bit of a diet this weekend.

[VaughanCustoms]

I got a couple random parts when I bought my bike and I have one air duct in this box but is there like a piece that goes on the inside to direct the air to the cylinder head or does it just funnel in air just through that outer piece? Anyone have any pictures of it?

[FJmonkey]

There is the exterior scoop that collects the air and an inner duct piece the directs it to the nearest inner part of the cylinder head.

http://www.ronayers.com/FAIRING-1-C287696.aspx

[ribbert]

As a general rule of thumb you want 4x the about of cooling out outlet than intake. So if you have 4 square inches of duct face going in you want to have 16 square inches coming out.

The ducts on the FJ work so well because they are designed along this principle. (Small inlet, lots of outlet area)

I understand that if you reduce the size of the outlet to 25% of the size of the inlet you increase velocity, but how does it increase volume?

Also, the FJ ducts go from large to small, not "small inlet, lots of outlet area"

Noel

[skymasteres]

As a general rule of thumb you want 4x the about of cooling out outlet than intake. So if you have 4 square inches of duct face going in you want to have 16 square inches coming out.

The ducts on the FJ work so well because they are designed along this principle. (Small inlet, lots of outlet area)

I understand that if you reduce the size of the outlet to 25% of the size of the inlet you increase velocity, but how does it increase volume?

Also, the FJ ducts go from large to small, not "small inlet, lots of outlet area"

Noel

Okay, so I royally botched my english there. You're right about the duct itself. It does taper which has a negative effect on volume but it does increase velocity. (Here they hve a huge amount of possative pressure to work with so I think the drag penalty was low on the list of optimization factors. Shooting for maximum cooling effect I tyhink) When I said lots of outlet area, I was including the area from the heads on. Not just the small outlet for the scoops. (It's not like the air stops there) In fact, the air pis rushing by the fins on the cylinder heads creating a low pressure region that would draw the air from the center out.


(I HATE the way the text editor on this site bounces UP AND DOWN like a mouse on crack!!!)