G-machine

ok heres the problem I have with this mod, is it makes sense at first to keep oil out of airbox but I tried it for a few days and realizied when I took off my oil cap that my motor has nowhere to vent air now? sure it keeps the oil out of airbox but where does the positive pressure go to? next thing you know is your blowing air and oil past the rings and blowing seals, think about it, if you take a air hose and blow it into a pop bottle with nowhere for the air to go what happens? the bottle will eventually pop! does this make sense to anyone or am I off my rocker? the motor needs somwhere to vent pressure! if Im wrong someone please explain why when this mod is done 10 minutes after you ride your bike and you take your oil cap off air comes out like crazy with the bike off? anyoneor did i do the mod wrong? basically you T all three vent hoses together on top of valve cover and remove the plug in valve correct?

wheelburns

guy all im saying is its been done for years and no issues just go with the flow buddy

tracetidwell

If you are just eliminating the hose to the airbox and t-ing it into the exhaust I would think that if the oil can make it into the exhaust to burn off that air can also make it in. If liquid can make it out I am sure air can make it in maybe you have something wrong somewhere I don't have this problem and my bike runs fine.

Ryan S

that air turns into ICE, therefore dropping to the bottom of your motor....giving negative pressure, kinda like a barometer

G-machine

my bike runs fine too but I still dont see why its a good idea to not give your positive pressure a place to vent? even if its into the atmoshphere with a catch can it has to be better than letting it build pressure in your motor eventually blowing seals and getting blow by past the rings? any real mechanics in the house? next time you ride your bike when you shut it off take of your oil cap right away and you will see what im talking about

onthacomeup

what is this air mod? can somebody explain it to me?...what is the purpose? why would oil go in the airbox?

G-machine

https://www.stuntlife.com/forums/443...r-box-mod.html

heres the link but I would be careful doing this! its good in the aspect of keeping oil out of airbox but I still think its bad the way its done. makes no sense to me on why you would not just vent pressure into the atmoshphere?

wheelburns

from a mechanical aspect i believe your right it would cause positive pressure in the crankcase. this could cause the things you talk about blow by and what not but i feel that its looked at as the lesser of 2 evils. oil in the airbox or some positive pressure. . . . im sure if you could come up with a way to do it where it vents to the atmosphere go for it

old man roger

i cant believe there is another thread about this if you read almost any of the other clean air threads you would know that doing the clean air mod correctly does not create pressure in the motor it actually creates a vacuum and redirects all the hot oily air away from your air box and into your exhaust ..

when done correctly the crankcase vent tube bypasses the air box and is ported to the exhaust through a set of reed valves in you valve cover , the reed valves are directional and will only allow suction from the exhaust so this pulls the hot oily air out of the crankcase and will vent it and any oil that makes it up the vent tube directly out the exhaust instead of into your air box ...

are you sure you are hearing pressure when you take off the cap and not suction ?

if you have pressure then you either hooked the hoses up wrong or didn't unplug your clean air valve when you did the mod ..

the clean air valve opens and closes when the bike is running and will create pressure in the motor if you don't disable it ..

old man roger

there is one other way you could get pressure but it is very uncommon and i doubt this is your problem but if the reed valves in your valve cover are completely clogged with carbon they could be stuck closed....unlikely but possible

repsolstuntin1

yo you have to have venilation in your motor if the mod does seal air tight your putting more and more pressure on your rings think about it?? the crank case vent that goes to the air box keeps the air pressure equal throughout the bottom end and if you get any moisture in the crank like living close to a body of water or whatever it wont vent it will rust anything not covered in oil and when the bike is just sitting thats just the very bottom end! That mod would be deadly to any motor!! thats just my 2 cents so whatev...

old man roger

proving my point that no one reads any thing but the first post

repsolstuntin1

yeah realized right after i posted it and read the rest of the posts......

old man roger

i should just save my post to note pad because i have typed it out so many times i cant count

old man roger

most stunt bikes have the tip over sensor [bank angle sensor] bypassed and they also usually have the idle turned up so in the case of an f4i if your bike crashes on the left side the oil from the crankcase can be pumped up the vent tube into the air box and when you stand the bike up still running all that oil gets sucked into your throttle body which can hydrolock your motor and cause the connecting rod to shoot out the front of the engine case ..

on other bikes like the 636 the vent tube is at the back of the motor so the oil can get to the air box just from parking the bike on the tail while the bike is still running ..

cjoec01

I read every page OMR, and look for your responses cause you know what your talking about. If too much oil standing @ 12 it goes out the exhaust, same with the air pressure I would assume, unless the factory T is still hooked up and working, a problem i encounter on my zx, cause there were no vac. lines just a plug that I left plugged in, it caused 2 leaks that went away after removing.

old man roger

exactly!!! , you have to disable the clean air valve or replace it with a t fitting

Captn. sProcKeT

Is there a way you can do this mod for a GSXR1000 k2 also???

When I do very long wheelies I get oil in the airbox....

old man roger

yes just bypass your air box and disable your clean air valve , i have never done a gsxr but there will be two big hoses connected to your air box one will go to your crankcase and the other will go to your clean air valve , connect them together...

the clean air valve will either be vacuum operated or electrically operated , if it's vacuum operated simply disconnect the vacuum line that goes to the valve and cap off the hose with a long screw and if it's electrically operated just unplug it ..

Captn. sProcKeT

Thanks, Will definitly try that...