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Breather bypass

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Old May 27, 2020 | 09:24 PM
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Default Breather bypass

Working on my breather bypass. Breather holes were filled with JB


Weld.
 
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Old May 28, 2020 | 01:05 PM
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That is a very compact and low profile breather bypass system you designed...

FWIW... I have done a breather bypass on four bikes...

The way you have your breather bolts vented/connected to each other, could allow for "puddling" on the one side, as the path is uphill to the other breather bolt...

In my bypass installs, I was always very careful to make sure that all hoses/fitting were lower/downhill from the beginning to the end....

Maybe not necessary, and certainly not as compact as your system..

Good luck with the mod....



 

Last edited by hattitude; May 28, 2020 at 01:07 PM.
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Old May 28, 2020 | 03:31 PM
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Yep, that is very nice and clean looking. I looked at doing mine that way originally, but the "puddling" possibility caused me not to. If Im thinking right, your forward mounting hole will have to fill up with oily residue before it can be pushed out and over to the rear mounting hole, which will just drain pretty much as anything comes in. But what I didn't know was what position the little breather hole in the bolt winds up being in when the bolt is tight. If when that bolt is tightened, the hole winds up between say 3 0'clock and 6 o'clock, is it going to matter that it then has to "breathe" thru that oily residue? Because in the forward mounting hole it would be below "water level, so to speak. Will it be of any concern, or will it still breathe just fine thru the accumulating oily stuff? Probably so, but i didn't know, so I went with a similar setup as Hattitude's... just oriented to the front, and looped tight so its almost all hidden behind the breather, except the one hose coming out in the front and goes to a catch can on the down tube. Also painted all fitting black so they disappear. Also, I tapped those breather passages in the back plate and put 1" 1/4-20 setscrews in them and locktite'd in place... that back plate cuts like butter.

 

Last edited by Ssitruc; May 28, 2020 at 03:39 PM.
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Old May 28, 2020 | 04:18 PM
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Looking into adding a DK Custom kit to my stock 2020 Heritage intake...had them on other bikes w/ after-market intake. How hard is the drilling on these cast parts?
 
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Old May 28, 2020 | 05:05 PM
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Originally Posted by Iceman24
Looking into adding a DK Custom kit to my stock 2020 Heritage intake...had them on other bikes w/ after-market intake. How hard is the drilling on these cast parts?
Not bad. Go slow, take your time and go easy. Cast can break really easy. If you tapping it, take it easy as well and clean out the tap frequently.
 
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Old May 28, 2020 | 05:09 PM
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I haven't done it, but I'd start with a smaller undersized bit and work up to whatever fittings being used. In the OP, are those 1/8 npt or 1/4?
 
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Old May 28, 2020 | 05:22 PM
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I bought the basic/discreet breather system to connect to HD's bolts & plan to drill through back-plate & route hoses down/below stock breather w/ external filter dangling under filter element. Thks f/ the guidance & I'll have to post pics when complete.

What's the worse that can happen...crack the back-plate & have to buy new/better intake...
 
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Old May 28, 2020 | 07:18 PM
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Factory vents are mid point 3 and 9 o’clock so I figured I was ok at 3/4 2 and 10 o’clock. Pipe size is 1/8 pipe. Go slow measure twice.
 
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Old May 28, 2020 | 08:11 PM
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OP? What size I.D. hose?
 
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Old May 28, 2020 | 08:16 PM
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With the breather bolts having a smaller diameter in the area where the exit hole is, I don't see where the position of where the bolts are "clocked" to be any issue?
 
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