Re: Airbox sealing question on 04-600 Its got holes in it OE

rotts4u said:
Today while prepping the bike for the upcoming land speed meet in 2 weeks I was looking at the airbox seals and trying to find a way to seal the junction between the airbox and the airtube connection. Many of the busa riders have removed the flanges on the airbox then made a flange that will seal up using a rubber intertube.

If you look at the junction the only thing that prevents the air from leaking out is the foam around the flange of the box.

So as I was looking at the whole deal I decided to take off the airbox and test it some more. So I taped up the throttle body holes and then using an air compressor and more sealing I blew air into one ram air tube.

I noted two holes in the bottom of the airbox that allow a fair amount of air to escape.These are toward the front of the airbox and are side by side. Anyone have any idea why they are there?

They are not the oil vents because those are all capped off with the clear vent hoses. I am wondering if they are for a vent to keep the box from over pressurizing if there can be such a thing.

Its not like the box can lift off the throttle bodies because the tank holds everything down. I am thinking of sealing those holes up.

Thoughts?

Don

Probably for water.

I'll have to check my air box next time in my '02. But I do have two small holes at the lowest point in my 750's air tubes for water to drain out.

 

They sound like water drains although I would think those would be at the back of the box . I say for what your doing plug them up more presure is more air , and with the right fuel that makes more power.An at 170mph the air in that box will seap from any crack it can

find.

 

IT already has holes with the clear plastic pipe on it for oil/water etc. I think there are 1-2 of those already but they are capped off but allow you to see if there is a problem.

Don

 

...how about sealing them using silicon (bathroom) sealant???

I used to run a 2001 Aprilia Mille and noticed that it had gaps between the plastic 'ram air' tubes and the frames holes leading to the airbox. I sealed these gaps up with sealant (dead easy) and made them air tight ensuring max airflow into the airbox.

N.

 

In the front of the airbox they are there to let the rain water out, if you have to ride in the rain. I would not seal them. Compare their size to the cross section of the two ram air tubes. They are so small that they will cause absolutley no pressure drop.

BTW, there should be similar water holes in the bottom side of the ram air tubes themselves.

 

The question I would want to know: At 160 or 170mph is the airbox at positive pressure, or negative? The engine is sucking down so much air at that RPM that the front RAM air ducts may only keep the pressure inside the airbox near 1 atmosphere. If this is the case, then the holes in the airbox will neither hinder nor help, but are just there. As someone mentioned above, two small holes have a TINY effect on the airbox pressure compared to the 2 big holes coming in, and the 4 big holes going out. Anyhow, would be nice to put a pressure transducer or something in the airbox and run the bike up to speed to see what was happening in the airbox.

j

 

The pressure tranducer in airbox thing was tested by some motorcycle magazines. Above about 100MPH the ram air starts to create positive pressure compared to atmospheric.

 

Re: Airbox sealing question on 04-600 Its got holes in it OE

I looked in my air box and the small holes are placed exactly at the lowest point just as the holes are in the air tubes. When water gets in the air tubes and box it needs a place to drain out so don't plug those holes unless you run the bike in dry weather and you don't wash it. In my opinion the air box and air tubes would not be at a disadvantage with the four small holes.

RAM air effect is not so critical that the box must be 100% sealed. Unless you can test this theory on a dyno then I wouldn't worry about the holes. Remember that the engine can only use so much air and the air box is designed with that in mind. I believe there are some racing air boxes available but they may or may not be dimensionally different, just made with less weight.

 

Re: Airbox sealing question on 04-600 Its got holes in it OE

rotts4u said:
IT already has holes with the clear plastic pipe on it for oil/water etc. I think there are 1-2 of those already but they are capped off but allow you to see if there is a problem.

Don

That capped off outlet is in the back of the air box after the air filter and would not be used as a drain for water. Maybe for an optional secondary device or service function of some type.

 

Re: Airbox sealing question on 04-600 Its got holes in it OE

That capped off outlet is in the back of the air box after the air filter and would not be used as a drain for water. Maybe for an optional secondary device or service function of some type.

Ok thanks I went ahead and blocked them up anyway.

 

yeah pretty cool huh? Ive been around here quite a while huh?

 

Yes, why revive it then? The guy you quoted isn't even active on the site anymore.