Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 851 / 888 > Air Filtration for Race Airbox / Air Intake

[851neil]

Steve & Phil, I've just recently installed my 1 piece carbon airbox (it's just the lower half) and it's sides and rear edge are butted up tight against the inside of the tank. Ok there will be some air leakage under pressure but it's near as dammit sealed.
This is where my interest is coming from with the front plate to close off the 'sharks mouth'. The foam I've installed, round the side edges of the tank is non breathable petro/oil resistant and provides an effective seal between the airbox and underside of the tank.
So it would seem that the rear and sides of the airbox are closed off and it will breathe through the carbon X tubes, there's only the mouth of the tank to resolve - to my reckoning this being closed off would make a rudimentary sealed/pressurised airbox ??
thoughts...

[phil911]

You're making confusion between quite airflow volume (851/888) and pressurised air volume (9** generations) ...

[phil911]

Here's the front part of the last generation of carbon fuel tank, 1994 mod.
The seals are original too ...
Even with these seals, you can imagine numerous leaks all around the tank body.
Pressurize wasn't the main goal of the ingeniors in charge of 851/888 developments, compare to 9** generations ...

[Mr. R]

Hi Neil, both Phill and i agree on the difference between the 888 + 916 type airbox systems.If you manage to build a completely sealed air box, then there should be a performance gain, providing it is large enough.Witness the gains of the early 916 over the late 888's,but the box needs to be as large as possible,which is why the factory altered the frame on the 916 style racers,748r's and 996/8 bikes to allow a bigger box to be fitted.Then you would get into the realms of worrying about loosing airbox capacity with the fitment of a foam in the box type filter, but i still think the small loss of 1 or 2 bhp on a road bike is a price worth paying,the gains which i think are two fold.1 protection from airborne dust etc, 2 in the event of a get off and the tank coming away the foam should prevent anything large from entering the throttles, after all we aren't racing these bikes( well not in a race series). Steve

[851neil]

Steve, nice point - I'm pursuing the sealed airbox path (Ok as sealed as possible) and am now going with chicken wire at the nosecone and I'll knock up some kind of panel filter to sit at the cross bracing just behind the headstock. In that way the airbox will have loads of filtered air to draw on and I don't take up airbox capacity with anything else.
Having said that, your over the throttle body solution / reality check warrants being considered at the very least !
cheers

Neil

[851neil]

This bike has a 955 motor and is using the carbon one piece airbox + carbon X intake tubes, as far as possible they have tried to go for a sealed airbox (I know the tank has a closed front on this bike). Also note the foam around the sides to try and close off the airbox against the tank underside.
Griff you mentioned action shots of bikes with the sharks mouth closed, I'll dig em out and post em up - may be a while getting this done though as I'm faced with a minor problem of a house move this weekend

[851neil]

errrm, might help if I attached the pic

[851neil]

Ok, still didn't get the house move done and dusted - chains are a pain in the proverbial...but heres a couple of pics just to show what I'm thinking of regards filtration
it's got to go in there - forward of the X bracing tubes & usual reg/rect mount.

[851neil]

and just a pic of the 3 stage filter in position - I'll be putting some mesh in front of the X bracings (behind the filter) so that the filter can't be sucked through into the airbox - I'll post when that arrangement is sorted...

[851neil]

oh and I've positioned the reg / rect in the middle of the carbon airtubes - just behind the ecu...