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Anyone doing the breather bypass on your M8?

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Anyone doing the breather bypass on your M8?

  #331  
Old 01-12-2019, 11:27 AM
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Originally Posted by Peter Quinn View Post


Sorry I'm not the Smart one arguing against the hundreds of engineering designers who have developed these engines for more than a hundred years.Im just agreeing with them and trying to get people not to listen to the self informed naysayers!
Like I said earlier, if the H-D engineers didn't have to put that **** back in there they wouldn't. I bet they will agree that the best place for that **** is any where but in the intake.
 
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  #332  
Old 01-12-2019, 01:36 PM
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A question for those of you that have installed cans that have to be emptied. Why? Why not run it under your bike and to the ground?
The amount coming out is negligible. You will run through 5 times what comes out in a couple hundred miles. (Those numbers are just WAG so take a pill)
 
  #333  
Old 01-12-2019, 03:37 PM
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Originally Posted by Cazador View Post
A question for those of you that have installed cans that have to be emptied. Why? Why not run it under your bike and to the ground?
The amount coming out is negligible. You will run through 5 times what comes out in a couple hundred miles. (Those numbers are just WAG so take a pill)
The goo will find it's way all over the underside of the bike and the rear wheel. Also when you park the bike in the garage you will need to remember to set an oilsorb pad under the area at the end of the hose. Seems that an external catch can that is easily accessed can be emptied without much fuss. Just my 2 cents.
 
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  #334  
Old 01-12-2019, 03:42 PM
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Originally Posted by Softy 103 View Post
Like I said earlier, if the H-D engineers didn't have to put that **** back in there they wouldn't. I bet they will agree that the best place for that **** is any where but in the intake.
Harley did not invent the system.More vehicles than you can imagine breathe out of the tappet covers through an oil restrictor directly back into the intake.Dont suppose these guys ever saw or worked on an oil bath air filter or an oil soaked paper filter either?
The pipes are called Breather pipes and not drain pipes for a reason! They breathe air with a small amount of oil vapor which requires vacuum to assist the breather function,reduce the casing pressure,and add to the upper cylinder lubrication.
Most importantly for the emissions control,it burns the the emissions within the combustion process and ensure it all passes through the exhaust.
Any attempt to close,catch or restrict the pipes or remove them from the inlet vacuum will collapse the system.
The yellow gunk is an externally manufactured emulsion of oil,air and water when they are trapped mixed and heated together as result of this or any other restriction.
 
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Old 01-12-2019, 05:50 PM
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Originally Posted by Peter Quinn View Post


Harley did not invent the system.More vehicles than you can imagine breathe out of the tappet covers through an oil restrictor directly back into the intake.Dont suppose these guys ever saw or worked on an oil bath air filter or an oil soaked paper filter either?
The pipes are called Breather pipes and not drain pipes for a reason! They breathe air with a small amount of oil vapor which requires vacuum to assist the breather function,reduce the casing pressure,and add to the upper cylinder lubrication.
Most importantly for the emissions control,it burns the the emissions within the combustion process and ensure it all passes through the exhaust.
Any attempt to close,catch or restrict the pipes or remove them from the inlet vacuum will collapse the system.
The yellow gunk is an externally manufactured emulsion of oil,air and water when they are trapped mixed and heated together as result of this or any other restriction.
For the sake of arguing, you run your **** the way you want, and I and a lot of others will do it the way we want. My pistons will remain clean and carbon free. As I said earlier I have seen first hand the difference in pistons with the breather lines going into the intake verses being vented away.
 
  #336  
Old 01-12-2019, 06:43 PM
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Originally Posted by Peter Quinn View Post
which requires vacuum to assist the breather function, reduce the casing pressure, and add to the upper cylinder lubrication.
False..
1) the system does not require vaccum to pull the pressurized air from the case - the air is pressurized and drives itself out.
2) the vacuum does nothing to reduce case pressure.
3) the vapor does nothing for upper cylinder lubrication. That is not how 4 stroke gas engines are designed. It's not a 2 stroke.

Originally Posted by Peter Quinn View Post
Any attempt to close,catch or restrict the pipes or remove them from the inlet vacuum will collapse the system.
Completely False. The system will not "collapse" if you do not run the breather tubes into the intake.
Again the introduction of EPA mandates is the only reason these gasses are directed into the intake to be burnt. Not because of a system or performance dependency. The system runs fine without it.

Bottom line, the breathers only point into the intake as a convenient place to dispose of the escaped gasses as to not hurt the environment.
Point of reference, older (before EVO) 4 stroke Harley engines did not have breathers going into the intake.
These gasses exited the bottom of the engine case (without vacuum) and went either into the primary or back to the oil bag or sometimes the ground.

That all said, does it matter? No. The engine does not care. You may care (about intake, valve, and piston cleanliness), and that's alright. America.
 

Last edited by lp; 01-12-2019 at 07:05 PM.
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  #337  
Old 01-12-2019, 07:50 PM
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The EPA is an enemy of the cumbustion motor
They would rather it was outlaw’d
They don’t care that their solutions hurt your motors. Take ethanol fuel into consideration
Manufacturers were forced to figure out how they could keep that crap from
destroying their engines.
aten years!
That what I give the combustion motor. Then its all electric from there.
gasoline will sell for pennies a gallon for a very long time before the stock piles are used up. So let them do what they will.
Just hang on to your bikes. Or better yet? Start collecting if you can.
 
  #338  
Old 01-12-2019, 09:29 PM
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I've been following this thread and some of the information/opinions are laughable. I subscribe to the external breather group and have been riding a HD since 72, well before the time when they started to vent the crankcase into the carburetor now throttle body. I simply vent to the ground and can also confirm that none of the vented oil ends up anywhere on my underside/saddlebags/tires. Granted I'm currently riding a 14 FLHTK so maybe the M8 vents more oil than the twin-cam 103 but I wouldn't think so. I think what really deters most folks from doing this mod has to do with warranty because it is illegal to modify an EPA requirement. Also I felt that it would be better to not have hot oxygen deprived gases being pumped directly into my stage 1 cold air intake..
 
  #339  
Old 01-13-2019, 12:48 AM
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Yada,Yada,Yada, Fake News.What is laughable is those of you that think you know better about breathers than the designers!
You think that the Yellow gunk,snot, or whatever you call it comes out of the engine? Notthing that comes out of the engine is harmful to the Bike but if you stick the pipe up your nose it will kill you.Your stupid attempts catch vapor restricts the expulsion of gasses which emulsify the oil and water.At any restriction point becomes a paint factory just like your nose when you have the Flu!
You do it your way,I'll go the Harley and the rest of the world way!
 
  #340  
Old 01-13-2019, 05:01 AM
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I don't know why I did not see this earlier I totally agree with Peter Quinn he is 100% correct
 
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