Part 1 Harley Breather Venting

Part 1 of a small series on how to decarb a Harley twin cam. Part 1 is all about re routing the vent lines from the intake manifold to the atmosphere stopping the build up of carbon and junk in the combustion chambers and on the valves. If you are having with your tunes going bad or pinging, rough idling, surging, hesitation, or just poor performance, maybe these short videos can be of assistance.

[@rogeryule3272]

Was looking to externally vent my '07 Street glide (big bore kit to 103"). Has 120K on it. Found your video and is the easiest, cleanest way I've seen. I couldn't believe how gunked-up my intake was. Hardest part for me was trying to drill out the plastic plugs, but I got there. My catch can hangs behind and below the backing plate, supported off the throttle body with zip ties. Now checking out part 2 and 3 for cleaning it up and de-carboning the poor thing. Then moving on to my '17 with the 124" kit and figuring out that set-up (lots of oil in that intake, but no gunk yet).

[@maxwellbricks7632]

Thank you for showing the 9/32 hose clears the air filter. I could not tell from looking at the pictures. You answered my question for my Roadster which I will put on a stage 1 filter now.

[@roryolson61]

Just found your video and I have the same setup on my 2007 FXSTC. This is exactly what I need to do! Thanks so much for your nice video. It looks easy enough that a caveman like me can do this! R

[@jhanlon1903]

did that to my 16 RK , i ran the tubes to a tee , then drilled a hole in the backing plate, then a tube to a breather that i put between the tappet blocks. bike runs great and NO crap going into the motor, only fresh air

[@jaimemelgar546]

Thanks so much for your video now I what to do I found your video this is the best ever I see and very cheap I think you are genius

[@RobertB56]

I did exactly as you did after seeing your video,works a treat

[@luisreneventura]

Thanks for doing this series of videos because I was about to do the same to my bike and looking at this is a BIG help!

[@mannymaddog2171]

Hey gozzie. Great mod and video. Thanks. You should continue to post Harley videos.

[@aurevoirbrielle8086]

Thanks for the vid! I had originally thought of drilling the plugs as you did, but I am reluctant to make permanent mods (even though it's just a rubber plug). It does seem to be the best way to "plug" the gap/hole left behind the filter. I have wasted some time indeed trying to figure another way to "plug" that gap, but I don't want to risk something coming loose and being sucked in the intake. Thanks again for the vid!

[@vabch82]

I used to run my oil at the full mark on the dip stick and would have moderate blow by in the catch can I installed on my '08 XL1200C. I installed an HD Oil Cooler kit and started running the oil 1/2 full on the dip stick. I change my oil every 3k and I hardly have any blow by in the catch can now. My Scoot has 44k on it

[@gozzie1004]

That's a good tip and I have read that more and more folks are lowering the oil level to prevent this.

[@TomTreeMan]

The best solution I’ve seen to manage accessible crank case oil is to run the lines upward tee them and run the single line into the inlet of a catch can positioned bottom in top out between the tank and frame, (inline fuel filter works) exit hose runs back down to the air cleaner, it quiets down the shissh shissh shissh that makes you crazy and its hidden under the fuel tank so it doesn’t have to be symmetrical for aesthetics. This allows oil film from the vapor separation to return to the system via the breather orifice during the negative pressure phase

[@Hoglife]

Same thing I did to my 03 Heritage Softail

[@2ndamendment770]

Thanks for the Info , I'm having some blow bi on my 99 heritage oil cap 80cu S&S , Ill try this out !

[@bryanr8314]

How did you drill the holes in the rubber breather plugs ?

[@thedieselpig4448]

You need to plug holes in back of plate or you get unfiltered air in the intake

[@danfecke]

Albert Backauskas which holes?

[@maddog7999]

dpf the holes where the original rubber crankcase vent tubes connected to on the backing plate of the air filter

[@kellyfulbright6521]

So did the mod help? I'm thinking about doing this to mine?

[@BATMANTHERIDER]

Hello. Thank s for the video. I got a question: do the bike is is still leaking oil thru the hose? My bike s running low in oil, and still leaks.

[@myawesomelife4168]

I'm doing this today on my 2003 Heritage Softail.

[@matthewmorrissey4756]

Let me know how it goes. I have a 95 Heritage and need advice.

[@myawesomelife4168]

Finished it and it helped and runs better and doesn't stall anymore. I ran the hoses between the cylinders and up the left side under the tank to the frame front down the left tube and put a clear fuel filter on the end of it. I feel safe riding in traffic now.

[@matthewmorrissey4756]

@@myawesomelife4168 Might have to try the same then.

[@tenoriopaintcollisiontenor4363]

Will that cause the oil pressure switch to pop popped the plastic piece right off

[@110americalovingpatriot2]

Sounds like ti our oil separators are plugged.

[@richardpitts6284]

Imagine if the guy filled his oil level to the mark ! To get enough oil so not to burn down the engine ! Well enabling the puking out into the air cleaner box ! Because of the 3 quart oil pan ? Unless you have a full dresser ! Than you have 5 quarts! Buy The Pan ? $ 1000 bucks ! Or double oil cooler's

[@guyconnell2250]

Unless you plug off the original breather hoses, you will still get oil in the intake. In other words the oil doesn't necessarily all go into the hoses you added.

[@johnnielsen5076]

Added hoses plug off the part of the original breather going into the throttle body.

[@gozzie1004]

You can see the whole article at www.hdforums.com/forum/general-topics-tech-tips/1119342-stop-sucking-oil-carbon-removal.html

[@hushjohnny9543]

Really good job bud'. I just run into a 95' Sportster that's blowing a little oil out of the same place...only its the stock air cleaner assy. with what looks like a K&N filter. I'm gonna' tyy to do what you've done to it. Good video! Thanks. ")

[@dzenx9861]

I have the same set up, I purchased a HD-1499 K&N filter which was a fit for the bike but with this “Round” set up and the thick bolts it is not looking like it will fit? Do you have any advice?

[@maddog7999]

round set up? thick bolts???

[@maddog7999]

but th original breather hoses are still run towards your throttle body???

[@shaneitsaname6135]

I've done this mod, the hose goes through the bung as pictured, there by blocking the entrance to the old tube that used to vent into the throttle body. Works perfectly.

[@travisgray3331]

So what size hole did you drill through the vent tubes?

[@maddog7999]

no holes should be necessary

[@TomTreeMan]

Breather gear gummed up

[@stizzoforizzo898]

Do i have the only oil tight harley on the planet? My bike never gives me a problem with anything at all nevermind leaking oil. How crazy is this world

[@adamb.6791]

Man, mine doesn't either, but it's a TC88. That said, this is the best and cheapest fix I've seen. I'll still do it to avoid carboning up my pistons, it really can do long term damage. Remember Harley makes money selling you a bike, they make MORE money selling you a second bike...and a third... otherwise they'd make them last forever.

[@MrPAULONEAL]

contaminants

[@stizzoforizzo898]

Is the whole world over filling their bikes and not acounting for the oil to expand when its hot. I noticed that every one of u guys are working on their bikes in a bike stand or lift. Thats a no no too daffy. Harley Davidson says that the oil level is checked hot and sitting on the jiffy stand. Ever notice that the dipstick has a ball joint to allow for the best read while the bike is leaning on the jiffy stand. If the bike is straight and the ball joint allows the dipstick to be vertical your gonna over fill the bike and then she will get hot and oil expands and wala ,it has no place to go but out of a breather or a gasket

[@jimmyjennings4089]

No contanament? You mean contamanent? Contaminated, contamination? Easy mistake unless it's a word that means something i don't know what the hell it is that's very possible, anyway back to what you were doing.

[@jonathansimmons5353]

normal isnt it..?? ;)

[@rezaarjmand7866]

need to speak up man.....

[@1silvervespa]

Aftermarket Garbage ....... Save your money.

[@adamb.6791]

You mean the $2 dollars he spend on 18 inches of hose? aftermarket what? thoughts? ideas?

[@benjohnson3700]

this is illegal

[@Chance-ry1hq]

Harley motors are such junk. You would never have this problem with any v twin other than a Harley.

[@maddog7999]

Savage no it absolutely does not. ive owned 3 v-twins. yamaha, victory, and harley

[@terrellgarren7125]

LOL. Dude, every non balanced crankcase has to breath or blow a gasket. Better to remain silent and be thought a fool than to speak and remove all doubt.

[@Chance-ry1hq]

@@terrellgarren7125 You probably should take your own advice.

[@johnmitchell9705]

This is bad for the environment, the ground water to be more clear. Every drop that goes on the ground ends up in our water. This is not responsible. You should invest in a catch can at least and recycle that crud.

[@theresawinzell1323]

Mnk

[@Savage-lx5yj]

Yep, well spoken!

[@maddog7999]

dont be such a whiny liberal. this little vtwin aint harming anything

[@docholiday1034]

Than dont do it pussy

[@dictumfactum9468]

The trouble with our Liberal friends is not that they're ignorant; it's just that they know so much that isn't so. RR