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Crank case venting fumes?(CD and others)

Discussion in 'Motorcycle Tech Talk' started by voodoo1, May 25, 2004.

  1. voodoo1

    voodoo1 New Member

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    Okay CD and others..I know there are EPA rules and such but the crank case fumes that vent directly into the air cleaner area means some of the "clean air" is actually not clean and robbing the bike of some power(o2wideglide factorycarb arleness bigsucker..gonna switch to the Screaming Beagle I think).the question is.. you should get the same results putting on an inexpensive acorn vent vs the hundred dollar sets I've seen offerered correct? I am under the impression it may increase a few hp(2-3) but overall it is helpful to longevity correct/performance.. and where to put(hide) the acorn vent?
  2. FriendGregory

    FriendGregory New Member

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    If you have enough dirty air ( blow by ) to make a 1 horse power difference, PM me with you address and I will sent $1 towards the dyno testing where you had it plumbed in and then not, no other changes.
    If you do have that much blowby, time for at least a cheepy rebuild; drop on a set of rings.
  3. chucktx

    chucktx Moderator Staff Member

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    you should not be getting enough "dirty" air to affect your preformance....if you are you have other problems.....but, to completley eliminate venting to the intake, there are kits avaliable to reroute it away from the intake..hope this helps...:)
  4. VYBR8ER

    VYBR8ER New Member

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    Here I spend big bucks everytime I try to get a few extra horses and all I had to do is dump my head breathers out to the atmosphere. Wish it were true on a sound engine. There's not enough contaminants in the flow from the head breathers to make a decernable difference in overall performance. Plus there is an added benefit of directing the airflow into the carb, what little bit of oil mist is in the air will not end up on the side or under your bike where you route the breathers. The Ness Big Sucker directs the flow through a nicely machined passage in the backplate. The Screaming Eagle unit uses rubber molded tubes to get the air/mist down the center of the carb/throttlebody. Either way they both work well if the oil pump is properly aligned.
  5. Killer-B

    Killer-B New Member

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    Hey voodoo, EPA! Who the phuck are they?

    Take the two vent holes that go to your football/air filter or what ever your using and block them off. Go to auto zone and buy a plastic ‘t’ and the appropriate size fuel line and reroute the lines from your heads, down the motor to the ground. (mother earth).
    I did this a few months ago to help with a carbon build up problem I was having.
    Last edited: Dec 14, 2007
  6. Killer-B

    Killer-B New Member

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    Oh ya, it cost about $6.
    No, you will not gain 2-3 H.P. Just piece of mind.
  7. Cracker

    Cracker New Member

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    Have to agree with Killer B here did the same thing not expensive to do, just plug the hole in the back plate & run rubber hose down between the motor & trans. Don't put anything on the end of it that can & will plug up, if you feel the need (I did not) to run the vent line into a small drip can go for it.

    Why in the world would you want to suck those fumes & grab back into your motor???
  8. hotroadking

    hotroadking Super Moderator Staff Member

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    You can run it open or to a small CCI filter to catch anything coming out, you have to clean that filter occasionally.

    Only reason you'd allow it to rebreath the fumes is envionmental, if you're the green type person, save the planet, global warming etc, then you would'nt want to route it to the atmosphere.

    Al Gore would be upset too.

    Otherwise the rubber hose routed between the motor and trans will do the trick, personally I don't think it does jack for performance, but I did it anyway.
  9. Cracker

    Cracker New Member

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    I vented mine away to help keep the inside of my intake & tops of my pistons from collecting carbon. Sucking in those fumes over time can reduce the combustion chamber & allows potential areas for pre-ignition to ignite. Not a big deal unless you are running CR at 10.1 or above PING.PING PING:eek:
  10. hotroadking

    hotroadking Super Moderator Staff Member

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    Funny I just took the motor down for some work, mines been vented 100% of the motors life, pistons have carbon on them, so does the combustion chamber.

    Not sure it really does much either way.
  11. chucktx

    chucktx Moderator Staff Member

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    my opinin on this is if you run hard, route the vent to the atmosphere....to eliminate the oil pudling in the aircleaner.....if ya ride normal, wipe it out on a reg basis and go about your fun!!!
  12. Tomflhrci98

    Tomflhrci98 Active Member

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    I think most of the blow by is caused when you slam the throttle shut and the intake sucks it in. The little umbrella seals don't work all that well.

    I'm with everyone else... ever since I routed it to the ground it has prevented a lot of problems and I don't get the puddle on the floor of my garage like I thought I would.

    On the carbon build up problem I think you are going to get carbon build up on the pistons regardless of what you do. I think this comes from the gas and unless you run lean you will always get some carbon on the pistons and valves.

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