What is the clean air mod on a F4I?
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#22
It doesn't create more vaccume because the two valves on the crank close under acceleration. Take your air box off and put your finger over the hose that connects the PAIR valve to the air box. You'll feel a slight vaccume. Now twist the throttle and you'll hear the valve close and the vaccume disappears.
There is an alternative that doesn't block the pcv. Just plug up the Pair valve system and leave the pcv in place.
Many people perform a variation of this mod because it allows for a more accurate air/fuel reading when tuning a bike. However, they only block off the PAIR system and not the pcv.
And as far as stunters go, this mod keeps oil from entering the air box if the bike gets laid down. However with this mod the oil would just go into the exhaust ports which doesn't sound good. alternatively you can keep oil from entering the air box by just venting the pcv externally by routing the hose elsewhere and putting a filter on it.
There is an alternative that doesn't block the pcv. Just plug up the Pair valve system and leave the pcv in place.
Many people perform a variation of this mod because it allows for a more accurate air/fuel reading when tuning a bike. However, they only block off the PAIR system and not the pcv.
And as far as stunters go, this mod keeps oil from entering the air box if the bike gets laid down. However with this mod the oil would just go into the exhaust ports which doesn't sound good. alternatively you can keep oil from entering the air box by just venting the pcv externally by routing the hose elsewhere and putting a filter on it.
Last edited by DBEAU; 04-01-2011 at 12:55 PM.
#23
It throws unburnt air/fuel back into to the intake system. Like I said it's Dyno proven mod so why would it be bad? Your hooking vent to vacuum pretty much in theory since the pair valve is just a tee now. As for the picture I just flipped the pair vavle around so all 3 lines can be hooked up and took the internal spring and washer out of the valve to act just like a tee(free instead of buying a tee) Plus you keep your pair valve plugging into your system.
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#30
just a few things a pcv valve helps vent .. i work on cars and went to mmi for bikes a vent is needed or you will blow seals and gaskest. i will stand my that till the day i die . and the reson for that .. is i worked at a dealer and this car kept blowing the valve cover gaskest long story short the pcv valve was pluged shut . so can you just put a stright where the pair goes .. ??? and keep the vent . the vent is needed.. thats like us breathing in a bubble with no way to get air in or out . and for the people who will say it gets freash air . think about it its sealed if it was not the bike would lose oil. .and another experance i had my turbo set up on my car i was at high rpms doing about 140 .. and the dip stick blow out and blew oil all over every thing . why you say . becase my pcv tube was too small the motor could not breath correctly..