Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > cutting back air vents

[scooter996]

I am considering going with a PIPERCROSS air filter OEM style in each air tube and have been told that I should also cut the air vents back about 7/8 to 1 back and take the gold color metal grates off the front. What are everyones thoughts?

[Edited on 23-7-2003 by scooter996]

[ducv2]

I've done it, but I doubt it makes much difference on a road bike, used a Dremel to cut back the faiing until it matched the start of the intakes. I did notice after removing the grids that they were half blocked with dead flies as its difficult to clean them properly. As I am using an 'over the bellmouth' filter, flies now end up swimming in alll the oil in the airbox.

[Shazaam!]

I also opened up the air intake ducts in the fairing. The main reason is that the total throttle body inlet area is about 3 sq. in but the stock duct openings are only about 2.5 sq. in. So the highest restriction of intake air flow on a superbike is right at these upper cowl inlet openings.

You can remove this flow restriction by using a Dremel cut-off wheel to remove about 1/2-inch of the outer (extreme left or right) perimeter of the pie slice-shaped openings. This gives an additional 0.5 sq. in. of inlet area. More drastic surgery will give you twice the improvement, but it's really unnecessary.

I also removed the stock air inlet decorative screens. I could have left them out, but the problem is that the inlet screens are an important part of the bike's air filter system. They prevent debris, insects and small rodents from entering the air tubes and clogging up the foam filters that, in turn, prevent everything smaller from entering the engine. (So keep the screens clean too.)

Since I use Pipercross filters in the air inlet runners, filter access and cleaning is a time-consuming process, so, I replaced the stock screens with a less flow restrictive aluminum window screening material. I figure that the flow area of the window screening material is more than double that of the stock grill. It sure lets a lot more light through.

Since the inlet screens quickly clog-up with debris and are somewhat difficult to clean, I also made removable pre-screens that are easier to clean - and as an added benefit - improve the air filtering without significantly limiting flow.

Here's how. Cut an additional piece of screening to fit the triangular intake opening. Leave an additional 1/4 in. all around to make tabs that fold back and hold the screen away from the screen on the fairing. The air pressure alone is enough keep them in place. Now all you have to do is to pull out the pre-screens for cleaning. The rear screens remain mostly clear of debris and are easily cleaned with compressed air.

[rcgbob44]

If its of any interst I replaced my folters with a JHP under the tank style air box filter a\nd after much cursing when fitting it, I beleive the results are worthwhile.
There is definitly more of a top end ruch than with the original filter system. I have also read with interst the threads about this style of filter and the effect of altering the resonance of the air box by effectively filling part of it with a filter.

I can only comment on my own results and they would appear to be possitive.

[scooter996]

To those of you who have cut the fairings back if you were to measure the bottom and sides of the vents after cutting it out how much surface area is let. Mine is about 1 inch left and was making sure that was enough before I put it back on.

[stimpy]

Mines cut back to leave about the same. You've got to remove the screens as they are by far the most restrictive part. The surface area of the screen must be in order of +40%. If you remove one and try blowing through it you'll see just how restrictive it is. Add a few bugs and the flow is even worse.With an undertank filter the bugs are not a worry. Mine really flys like this. With the Casoli filter it also sounds way better and looks cool..