External Breather
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
That looks really good and professional.
Just one caution, since there is a lot of it that goes uphill or is angled upward instead of downward, the vent lines may fill with oil over time which will degrade it's ability to vent air.
To check that it's still venting correctly, run the engine for a bit, get it hot, shutdown and unscrew the oil fill cap. If air rushes out like air from a balloon, you know your not venting correctly.
Here's to hoping it all works fine - probably will.
Just one caution, since there is a lot of it that goes uphill or is angled upward instead of downward, the vent lines may fill with oil over time which will degrade it's ability to vent air.
To check that it's still venting correctly, run the engine for a bit, get it hot, shutdown and unscrew the oil fill cap. If air rushes out like air from a balloon, you know your not venting correctly.
Here's to hoping it all works fine - probably will.
Club Member
Joined: Jan 2007
Posts: 3,551
Likes: 1,929
From: NE Florida
Looks great!
How much crud to you collect in the Air Oil Separator?
I ask because it looks like you created an airtight system. Air Oil Separators work differently than Oil Catch Cans. AOS's work by passing the contents through the inlet and having an outlet and dropping oil, water, etc into the can. OCC's work by allowing the breather pressure to push the air/oil/water/etc. through the tubing and into the can which is why there is a breather on top of the can.
How much crud to you collect in the Air Oil Separator?
I ask because it looks like you created an airtight system. Air Oil Separators work differently than Oil Catch Cans. AOS's work by passing the contents through the inlet and having an outlet and dropping oil, water, etc into the can. OCC's work by allowing the breather pressure to push the air/oil/water/etc. through the tubing and into the can which is why there is a breather on top of the can.
Ultimate HDF Member
Joined: Nov 2005
Posts: 5,926
Likes: 138
From: NE Ohio
Looks great!
How much crud to you collect in the Air Oil Separator?
I ask because it looks like you created an airtight system. Air Oil Separators work differently than Oil Catch Cans. AOS's work by passing the contents through the inlet and having an outlet and dropping oil, water, etc into the can. OCC's work by allowing the breather pressure to push the air/oil/water/etc. through the tubing and into the can which is why there is a breather on top of the can.
How much crud to you collect in the Air Oil Separator?
I ask because it looks like you created an airtight system. Air Oil Separators work differently than Oil Catch Cans. AOS's work by passing the contents through the inlet and having an outlet and dropping oil, water, etc into the can. OCC's work by allowing the breather pressure to push the air/oil/water/etc. through the tubing and into the can which is why there is a breather on top of the can.
.
Cruiser
Joined: Nov 2014
Posts: 171
Likes: 7
From: Royal Oak, Michigan
I have a FM stage 1 a/c, and ran vacuum hose from the breather bolts to the bottom of the a/c, drilled a hole through the back plate, then used a T fitting to connect from there to a fuel hose running across the front of the engine into a catch can (from Wimmer Custom Cycle) attached to the left down tube, with optional pet **** for easy drainage. Works well, and with fairing lowers the whole set up is hardly noticeable.
https://www.wimmercustomcycle.com/Puke-Cans-1.php
https://www.wimmercustomcycle.com/Puke-Cans-1.php
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
Road Warrior
Joined: Aug 2013
Posts: 1,619
Likes: 57
From: New York
I have a FM stage 1 a/c, and ran vacuum hose from the breather bolts to the bottom of the a/c, drilled a hole through the back plate, then used a T fitting to connect from there to a fuel hose running across the front of the engine into a catch can (from Wimmer Custom Cycle) attached to the left down tube, with optional pet **** for easy drainage. Works well, and with fairing lowers the whole set up is hardly noticeable.
https://www.wimmercustomcycle.com/Puke-Cans-1.php
https://www.wimmercustomcycle.com/Puke-Cans-1.php
