Why Your Harley-Davidson Needs a Catch Can or External Breather System

[@GixxerFoo]

Would you run a catch can, external breather or just opt to clean your top end every now and again?

[@64Goef]

I run it without a catch can. And oil half to 3/4 on the dipstick hot. No problems with any oil/water sludge venting.

[@danfecke]

Every ice engine should have one.

[@karateman856]

I run a catch can on my dyna.

[@2trdmustanggtfordf1hdsgsfa80]

Just completed install of DK catch can after engine kit and rebuild. Simple drill and tap operation.

[@parkersgarage4216]

id run a catch can as i do on my srt8.

[@WeLive2Explore]

I’m just sitting here waiting for that shelf to give.

[@GixxerFoo]

Lol I always was too, finally got that thing replaced now.

[@IntoTheWildernessBushcraft]

😂

[@richardbeto1615]

🤣🤣🤣

[@stevenbarrett7071]

🙃

[@v3exceed]

I was watching that too.. gave me pause on the advice, but its good advice. My buddy just got his done, I'll need to put some time aside to do it.

[@mark-1234]

As someone who's been a mechanic for over 40 years, I think I'm going to contest a few things here. For one, some carbon build-up is normal on an engine that's not making long highway runs. Two, the amount of crankcase air going into that intake is pretty minimal unless you've got some blow-by problems. If you've got heavy deposits, think rings or too rich a fuel mixture. Third, a drip or two of oil on the pavement from a breather vent is hardly going to cause you to lose control. Otherwise, I do appreciate your videos. And you're right, many DI engines do build up an excessive amount of carbon.

[@gnsmk357]

One less job to pay some one to fix is alright with me. Some people are ok with almost good the rest of us like to get it right the first time.

[@fire_titan5735]

​@@gnsmk357 the entire Harley Vtwin success is built around it's imperfect angle

[@grimeyhonkyracing3938]

I run the hose into my helmet on long trips

[@johnkolinoff8591]

Good one.

[@kato64]

🤣🤣

[@125saito]

Now that's funny right there.

[@ALLofYOU2]

Once you go black you dont come back

[@pmak10]

Great video as usual! I did the mod on my 09 EG. It only has 3k on it but I figured I'd head off any problems. I posted the pictures on one of the forums I belong to. I got a lot of positive feedback. One of the members thought it is going to create issues with oiling. I don't fully understand what he's talking about but perhaps you can explain. I definitely don't want to hurt the engine. Here is what he wrote: A "catch can" has a vacuum pull on it still,to keep the engine in that vacuum state,definitely needs it.! Your actually gonna CREATE pressure (vs. a vacuum) and make your engine have excessive oil building up,and possibly causing a pumping issue. So,get a true "catch can" and route a hose back to the INSIDE of air cleaner to keep a vacuum. Only in a positively charged intake do you not run a pcv setup,or it's on a one-way check valve.

[@dmitrykhramov1832]

Yeah, there is a lot of talk on the internet and you tube on the subject. Even Doc Harley admitted the issue ( surprisingly)! I didn’t realize it at first but it all makes perfect sense 👌

[@benscratchin8014]

Here's the link you're talking about. kzbin.info/www/bejne/gqC5poKrnaupetU

[@asquared7861]

Good tip with the over night soak. Gonna try that out.

[@araneaetvelivolum1086]

I took an Arlen Ness Heavy breather backing plate, cut off the two mounts to the engine, and then used banjo bolts to install my catch can . The air cleaner backing plate holds nicely with the three bolts around the throttle body.

[@n4zou]

Google "EMPI breather box". It's made for air cooled VW engine's but will work on Harley's as well. You'll need to fab a mount for it and figure out where to put it. It has a foam filter that you put a little oil in when you install it but after that the oil in the vented air keeps It wet. You can run a hose to the air cleaner from the box but it's designed to vent without needing to do that. It will produce a distinctive smell if you don't run a line to the air cleaner. Two screws hold the cover over the foam filter so it's easy to service. Wash the foam out with gasoline and apply oil when needed. It will cure your venting problems.

[@jeremymacklem2510]

Great video sir! I found an external breather made by Kuryakyn for my 2000 Deuce (TC88B)...it separates the oil from the air and only air is vented. I will find a part number and leave it in the comments 👍

[@garyboman5018]

Good topic. I just got done converting the Ventilator a/c on my 110" Slim and my 2020 Road King Standard by watching KZbin vids and the DK Customs kits. After seeing what the oil mist can do to my pistons in a short period of time, it just makes since. I modified my RK stock airbox by opening up the bottom and adding some more stainless screen along with a KN 1717 filter and routing the breather tube through the bottom of the box. Looks almost factory! For an inexpensive but attractive catch can, pick up an aluminum brake resovoir from EBay that has the small bracket attached. You'll be mounting this upside down with the screw off cap at the bottom. Drill some small holes on the top (bottom) of the resovoir, plug in your hose, and mount it using one of the cam cover bolts. To clean it, just unscrew the cap (which is now the bottom of the catch can). Thanks to Gingybeard for that idea.

[@lanceandmelanierogers6255]

At 6:28 a can disappears in the background on that damm shelf.. lol

[@slickrick4202]

Yea it does!! No shit!! Good eye mate!! I think it’s the can he shows to spray in the head

[@125saito]

And magically at 7:50 it reappears!!

[@lowkeybuilds9075]

Lmfao......that's funny holy shit

[@milmex317th]

I see shit like that in alot of videos, at first I thought I was tripping But I've never did LSD Now I don't even pay attention to someone else's editing job.

[@bv.hd883]

That can was too full and needed to be removed prevemptively in order to avoid a disaster XD

[@jocrp6]

Also, oil ingestion or oil mist in engines lowers fuel octane.

[@christopherdean1326]

Glad I found this video! I bought a '94 S&S Sportster a while ago. It had the S&S air cleaner on it, and I've never really cared for them, too big and bulky imho. Got a nice little wire cleaner, but it left the breather bolts open. As an engineer, empty bolt holes offend my eye, but I wasn't sure what best to replace the breather system with. I think I will, after watching this, try the set up you show at 3:00, they seem to be available over here in the UK. Thanks for the info!

[@rogermcwilliams6302]

I run Marvel Mystery in my road king every other fill up!

[@andyd8185]

Great video... I think we all would like you to do an evo , twin and M8 demo of an air breather so we can see what you think is the best way to mode your Harley. Cheers

[@FXFBS540]

Been meaning to do this on my M8 Fat Bob, been venting to atmosphere for years on my sportster.

[@louisgoldfond6326]

Another great video buddy. Took ur advice on the Woods cam for my 07 street glide 96. With install and a good tune with my Power Commander V. Bike runs really really nice. Thx for the great video on that. This video was a good one as well. Very informative. Be well. Keep up the great work

[@GixxerFoo]

Thank you! I appreciate it! That's awesome to hear! A good cam makes a big difference!

[@thechiefengineer5886]

Im running a classic s&s teardrop aircleaner on my twin cam , it gives you the option to go external or internal couse its runs hoses from breather bolts to intake .... no need drill and tap ... just add hose 👍

[@GixxerFoo]

Is that with a fuel injected bike?

[@thechiefengineer5886]

@@GixxerFoo yes its a 2013 street bob , 96” (still 96”)

[@shaunallen8902]

DK Customs has complete systems, several varieties of Breathers and external venting systems. They work great on my bike . Their KZbin channel also explains their systems. Thanks GixxerFoo for bringing this up and thanks for all the highly knowledgeable tech advice . Love your channel man!

[@mayoman8565]

Gold wings don't need that junk . yuk

[@bradleyyounger8499]

Omc makes something called engine tuner to clean out carbon that works amazing! You can get it at marinas

[@GixxerFoo]

I'm gonna have to check that stuff out, anything that makes getting pistons cleaned up easier!

[@robbyclark6915]

There are actually people on KZbin arguing that this is a nonissue. That’s their opinion and they can do whatever they want. My thought is that it’s easy to do and cheap as well (easy if you go with DK customs anyway) why wouldn’t I do it if it helps out my engine? I got an air cleaner from DK and breather bolts and it was super easy and cheap and I’m not sucking hot air back into the engine. That’s nothing but a win. I also put a vied fuel management device on the bike instead of an expensive tuner due to the extra air flow into the engine. It moderates the air/fuel mixture for a stage 1 and is about a third of the cost of a tuner.

[@GixxerFoo]

Bikes will run fine without one and put a lot of miles on the motor as well. I guess you could argue it as a non issue there. However, the carbon build up on the pistons robs horsepower and in some cases can lead to serious issues.

[@SaddleTrampTV]

I've used two different sets of external breather bolts on my chopper before and found that they can be pretty messy in the long run. Now both the Tramp and the Heritage have the external tubing running from one head over top the carburetor to the next head with the line running down behind the engine. I eventually plan to do the same with the electraglide.

[@GixxerFoo]

It really does keep the carbon off your pistons, makes a big difference!

[@chrisdawson8252]

Evo Forevo

[@dwaynehollar6834]

I have 2003 fatboy and when I purchased this it was the first bike I've been on.its been done to the 9's and it has a Doherty breather, I also have delphi fuel injection and possibly need a special umbrella valve with 2 chambers. I'm wondering about the Doherty breather. I heard they were out of business. I've had swveral backyard mechanics and am trying to find a parts list to my Doherty breather with vents. The last person to service bike cut hose & took off jets and I found that none of the bolts were not torqued and 1/2 of the nylon washers, gaskets ,& rubber seals were lit there.

[@robertlumsden942]

But think about it. positive crank case ventilation for cars has been around for over 40 years. i dont think it is a major problem. I had a corvette back in early 70 and it had one. PCV valve. :)

[@mrnonpc9885]

Regarding top cylinder cleaning product: Have you ever tried spraying oven cleaner in the spark plug holes to remove the carbon?

[@motorcitymadman146]

You need to block off any holes in the back of the intake plate or is will be sucking air through them.

[@08StreetGlide]

Sorry, can't drop a like, I'm watching again....you need a second like button....already hit the first....

[@GixxerFoo]

Hell l appreciate that! Thank you!

[@oldbiker9739]

my last 4 Harleys all had a crank breathers installed, no fouled plugs or carboned up valves , all have over 200,000 km on them in Alberta Canada not sure about the 99 softail my son has now , but he is having problems with oil fouled plugs and piston carbon .

[@GixxerFoo]

Having that stuff routed to where it's not going back into your intake makes a big difference!

[@georgeguidish7342]

I am not watching anymore until that shelf gets fixed. Your killin me smalls!!

[@GixxerFoo]

Lol the shelf has been replaced!

[@georgeguidish7342]

@@GixxerFoo 👍I am back in!

[@kujansu]

HAHAHAHAAHAHA I was waiting for it to fall

[@harleyhawk7959]

guy doing my motor on my 05 U.C. I asked. his opinion was unless you are spanking your motor alot, maybe yes. if you are using your bike as a cruiser, his opinion, as long your not lugging your motor, like some riders do. lugging down the rpm just to get that lop. then yes you are going to have unburned carbon build. drop a gear keep the rpm up. he has 30 yrs wrenching harley motors.

[@GixxerFoo]

If you keep the bike cleaned out you won't end up with a oily top end, carbon black is pretty much unavoidable.

[@timdavis8154]

I ordered a DK catch can.

[@brucesantacory1390]

you are aware that carbon build up happens just by the engine running, i'm a Retired Harley Service Manager and i've seen the same carbon build up on bike that NEVER had the same breather set up, and rather then changing the stock set up adding a little Additive like a Lucas fuel treatment you'll get better results than the catch cans and filter systems

[@robbyclark6915]

How often should you use this fuel treatment?

[@robertglancy4474]

@@robbyclark6915 I know I throw in a cap full or so of Marvel Mystery Oil about every other tank fill. I also will toss in some Startron treatment as well because right now I am only riding on the weekends. But I am changing the oil soon and saw his thing and I am thinking of giving it a try, don't think it could hurt.

[@GixxerFoo]

I use a cap marvel too in my bikes every now and again. I do a cleaning every oil change on my bikes too. Chevrolet Dealers used to do it on their 5.3 engines when they started pinging from the active fuel management spraying oil into the combustion chamber. Cleaned the carbon off the pistons and got you down the road, but didn't fix the actual afm problem.

[@drumsnbass]

How much are you spraying in there for overnight cleaning?

[@romulouchoa8217]

Seu vídeo tem a melhor explicação sobre o assunto , sou Brasileiro, aqui temos muitas dificuldade em manutenção das harleys , eu mesmo estou com problema no M8 2018 , correndo aqui pra resolver

[@djmysticalone321]

Just drive it when it breaks it brakes

[@chopperchopster]

i just run to atmosphere . I have never let it go to the air cleaner. They dont inspect motorcycles here in Arizona. You can I believe put a crank vent on K&N used to make them maybe they still do? I dont even do that . I just a run a piece of hose to under the bike. On my chain drive stuff I use it as a chain oiler! [choppers I build] Screw the EPA.

[@GixxerFoo]

That's the way it used to be done back in the day with the chain oiler system!

[@TomGlander]

On my 23 Road Glide ST I vented the crankcase cover only. This has taken pressure off and there’s no misting in the intake. This is after 1600 miles. No need to vent breathers on this M8.

[@chrisdawson8252]

Great video. Thanks for taking the time to explain things and mentioning multiple options. I know it's bad but I still think it's not "that" bad. Only time can tell. I do agree external breather and re-tune is the way to go.

[@jjbigwheel]

good video, thx. You should do a before and after piston cleaning and show us the results.

[@Nasty72C10]

finally i'm not the only one. all my harley's beath into an external catch can the 2nd i get them new or a new to me and i rebuild it , i even do it on my new cars right off teh lot to my shop so i can machine a catch can, they are worth the investment i've rebuilt many harleys and from the butterfly back is just coated with shit oily water mess . i show my customers what mine looks like after beating it to death at he track for 7 years and its clean as can be inside especially if you like to rev it up

[@GixxerFoo]

That's the way to do it, honestly not a bad idea going through any used bike. I like to get them cheap with a lot of miles and freshen up the engine, it's like a new bike after being gone through.

[@westoniii]

I run that little hose to dump on the chain. 2 birds one stone.

[@GixxerFoo]

Hey that's one way to recycle!

[@dalepatnode8258]

Do Indians have all of the issues that Harley? I have a 2014 street glide with 18000 miles. I haven't had any problems but feel in sitting in a ticking time bomb.

[@GixxerFoo]

The Indians have the same breather setup where the crankcase is vented through the heads. The 2014 103 is actually a really good engine, the late model 103's they got it right.

[@davidm6975]

Don’t do this!!! You will have lost all back pressure that you need to pull oil down in motor!! Bad idea

[@GixxerFoo]

The oil is pumped through the engine via the oil pump and returns to the sump by gravity. We see a lot of issues with the new M8 engine and it's inability to relieve crank case pressure which forces the oil vapor past the rings and causes the sumping issue.

[@MrMike-qn4xn]

DK customs wants $171 for an external breather system (for my 2008 Road King). A roll of hose, a small can, and some fittings. Insane!😮

[@GixxerFoo]

That is pretty high, you can get catch cans on ebay or amazon and build your own pretty inexpensively.

[@charliedee9276]

My early 91 Evo is a bottom breather, pukes on the ground like a proper Harley is supposed to!

[@GixxerFoo]

Leaving the mark of a true Harley!

[@charliedee9276]

Actually it used to, I set up a home made catch can/breather system on it. The PO had it just puking on the ground due to a Ness backing plate installed with no provision for the breather tube. I have a similar system on my ironhead as well.

[@johnjohnson2855]

It’s not illegal to make its illegal to use. 😬

[@wolfemanbog4176]

How about car injectors fuel treatment will that help

[@GixxerFoo]

Yeah can run some of that and l do often, like Lucas or sometimes Amsoil Quick Shot. It helps a little bit hit actually top cylinder cleaner really gets it knocked off.

[@slickrick4202]

Thank you !!! Finally people are talking about this huge issue & figuring things out!!

[@briankoons2266]

A bought a Arlen Ness stage 1 big sucker kit and the plugs are closed off. Is that a bad thing or ok? There closed breather bolts that hold the backing plate on.

[@GixxerFoo]

That's where you have to get creative and bypass those breathers to a catch can.

[@briankoons2266]

I put a Drag Specialtys breather kit and a Dragtron 2 air cleaner filter. It looks awesome and getting better performance!!

[@frankqu1427]

I own 2 bikes 1 fuel injection and 1 with a carb. I converted both with external breathers. The fuel injected bike ( sportster ) throttle body was very nasty so I cleaned it with throttle body cleaner and then converted it to an external breather. I had to do some drilling in the backing plate to reroute hoses and then join them with an external T fitting and then routed a hose under the bike with a external breather which I tied to the bottom of the frame with cable ties. Total cost to do each bike was between 20 and 25.00 each. The external breather is available at just about all auto parts stores and cost 12.99. They also have the hoses sold by the foot. The only word of caution I have is when drilling the holes in the back plate to route the hoses through is to drill the hole size as close as you can to the size of the hose you are using. If the hole is to large there is a danger of sucking in a foreign object into the throttle body or carb and possibly doing engine damage. I would not recommend using any kind of sealant around the hose for fear of the same consequence. Just drill the hole where the hose fits through it snuggly. I immediately could tell a HUGE difference in performance on the bike that was fuel injected. I have a power commander 5 on the bike and I didn't have to get it retuned. The bike with the carb I couldn't tell any difference because it was very clean inside. I probably didn't have to convert that one but it was so easy I decided to do it anyway. I apologize for the length of my comment. I highly recommend the conversion.

[@bradduffield9603]

Great information. Thanks for the options available.

[@divine_swine9665]

Good info here. I bought an external breather from DK in the fall. I haven’t put it on yet... it’s been too cold out there since my garage isn’t heated. But it’s looking like I’m gonna have a chance to get out there this week. I’m thinking I should clean my pistons prior to doing this tho.

[@chrismiller9032]

My 76 Triumph Bonneville had the PCV setup where the tube emptied behind the rear tire. Perhaps a little ahead of its time but not likely EPA compliant.

[@phillipmckeownakalucifer.6689]

When are going to cover the 2021 m8 114. Im sick and tired of all the dead dogs already ...

[@GixxerFoo]

I have a video on the 114 with some bolt in cams here kzbin.info/www/bejne/Y2jbo6pjYtmMaMU

[@pb68slab18]

So how do you know if that burnt oil on the pistons is from breather issues, or bad valve seals and or worn valve guides? Quite common on air-cooled motors. Viton or teflon seals hold up much better than stock.

[@semperfipar1299]

What??? Cars do not have a problem with direct injection. Indians and Victories and every other motorcycle besides a Harley have direct injection and they too do not have a problem. If you have carbon build up, which was common in old carbureted engines, you took them out and floored them to blow the carbon out of the engine. My sportster still runs like a raped ape and I never had to put a oil catch system on it.

[@AmosBHaven]

"Catch Can" "Puke Tank" "Catch Can" "Puke Tank" "Mini Puke Tank!" Some "rice burners" go so far as to have a hose that is clipped off down by the rear wheel. Every now and then? Undo the clip and let her drip! Into a "Catch Can" of course!

[@jamessouthworth1699]

Have you noticed a visible Improvement in carbon after using the cleaner in the cylinder?

[@crockett11000]

I did a bypass on my new 2022 114 right off from the show room floor with 9 miles on it!. I don't want that crap going in my new engine!.. And not just engine oil, and vented crank case air but condensation/water that builds up from changing temps!. And No it will Not affect the stock tune. The ECM has a 10% self adjusting differential.. Even if i put on a full free breathing stage 1 type air cleaner and and slip on's, It will run just fine! See DK customs dyno run and Stats on M-8s !!!. Nobody should be getting that much oil comming out your breathers or your by pass hose. Unless you over filled or engine oil level is too high!, There has been a few other problems of excess oil comming out due to sumping, poor compression/blow by. Other than that, oil on your rear tire? Their better not be that much comming out to do fooking squat! And if ya did their wouldn't be any oil left in your engine at all!!!. And a tiny bit of oil on the bottom of your frame, Well better than rust!!.

[@johnkessler9878]

Would this apply to car, truck engines? Is that why people do an egr block off?

[@GixxerFoo]

Blocking the EGR on a car or truck keeps exhaust gas from being pumped back into the air intake which does pick up a few horsepower and that's essentially what we are doing here on bikes too. On a car you're referring to the PCV being run through a catch can and yes this is a must do on today direct injected vehicles. Your intake valves on direct injected vehicles don't get cleaned anymore by the fuel and they coke up really bad with oil over time. It's not a bad idea at all to run a catch can on your car or truck too as well as your bike.

[@richardrussell500]

No need for a retune on an M8... these engines have a richer AF setup compared to the TC. I use Amsoil Quick shot at every refill. It fights ethanol fuels and also helps clean the carbon buildup. I run the DK Customs external breather and my bike runs much better than without it.

[@billgonzales8978]

dont ever xomplain if your harley leaks oil, thats normal

[@GixxerFoo]

Back in the day it was, if anything Evo and up is leaking you might wanna check that out lol.

[@user-wj6kq3xw2g]

Lil seafoam will clean up the pistons

[@robertbobby2410]

They're saying that the Harley-Davidson the calibration has not been done properly on their motorcycles

[@hawkdsl]

absolutely do a catch can. Doesn't cost much, but may limit air cleaner options. I run a Forcewinder with a "Y" to a catch can on the left side. Usually only have to clean it out once a year.

[@theodavies8754]

Every 25 years read the factory manual to find out how long you have been doing it wrong.

[@vancedyer755]

Hey Gixxer, I just installed a DK Customs DIY external breather system into my 2009 FLHTCU. I have a SE Chisel air intake, I drilled into the ears of the base mount where the brass fitting are now installed, aiming up around the 2 o'clock position. I filled the oil channels in the base with RTV. I'm running the house up under the tank and then down under the coils to the right side of the bike just behind the side cover on a plastic shelf where the breather filter is now velcro'd into place. If it gets messy I'll set it in a small plastic rubbermaid bowl or get the catch can.

[@stevechoi7837]

I have vrod with breather on rear engine separately. But I still couldn't figure out how to put external breather on front engine. Suggestion?

[@SgtBFGunner]

Bro, you have to be closely related to Scotty Klimer. 😎👍 Great videos, thank you!

[@boomerguy9935]

I did this to my carbureted Sportster XL883 several years ago without a filter or catch can on the drain tube. I did have my stock air filter housing modified but I eventually switched over to the Drag Specialties carb support plate and crankcase vent system plus a TC BROS air filter kit which I like even more. The drain hose runs down through the swing arm and exits about 2" below it. My 883 vents such a small amount of oil that after I park it and place a paper towel underneath the drain hose, only one or two teardrop spots will appear in the next several hours. Different bikes may vary in the amount of condensation but it's no problem with my bike. I've never found any oil on the tires or frame. My air filter stays completely dry and so does my air intake in the carb.

[@steelbender58]

Took my twin cam 88 to the shop for carb tune. Mechanic asked what that shit is i had rigged up on my bike. I said crankcase vent. He shook his head and asked if i would like to blow the seals out of my engine. No ,i said. He said old shovelheads might get away with this but not newer bikes. He been a mechanic 40 years. Go ahead and fk up your harley with this garbage. I removed that shit. Only had it on there a few days. Newer bikes need suction to pull that crap outta the engine. My bike is 20 years old and its running fine the way the harley engineers designed it

[@tssci6774]

The PCV system serves to pull blowby gases and oil vapor, moisture out of the crankcase. Having a slight vaccum conditions drastically reduces varnish, carbon in the engine. Anyone that has worked on 60's era down draft vent systems no how dirty these engines became. Also having a vacuum in the crankcase creates better sealing of the rings and gaskets. I removed the PCV system on my 80 buick V6, and went with only breathers, what a disaster that was. I learned the importance of a positive ventilation. The carbon on the top of pistons is caused by poor fuel. Do t yse ethanol if at all possible, it reduces power, requires more fuel. The carbon in those pics are fuel based. Use a Top Tier, 91/93 octane fuel which had max detergents. The small amount of air being drawn out of your crankcase isnt going to throw off your tune or A/F mixture. Dont use fuel additives which has oil in them, they are far more worse than small amount of oil mist that cones through PCV system. I tried Amsoil PI, and it gummed up my pistons instead of cleaning. A proper Italuan Tune up will remove safely remove carbon. I agree about changing oil after a cleaning, Ive done oil analysis and it really contaminents the oil, and takes 2 oil changes to get it running clean again.

[@Hodado]

TC 88 stock puking oil after about 2 hours would a catch can remedy this?

[@pg981]

Sea foam 👌

[@keeto56]

Interesting video. My FXR is a bottom breather so most of this doesn't apply.

[@arthurlynch1549]

a bit late coming to this i live in londonderry northern ireland and on my own as far as bike concerned i have 2004 flstci six speed have changed the camchest tensioners to hydraulic what want to know is can i put two catch cans on existing stock rubber breather hose and hide behind ai rfilter housing has stage one k n filter 43000 mls thanks in advance great channel learned a lot

[@TheWolfsnack]

Fuel injection? Never had one...ever...don't want it...

[@michaelhayward7572]

I would'nt say carbon free piston crowns.... All my bikes vent either into atmosphere or into a large diameter frame tube. My Triumph has non timed crankcase and top end breathers. They still have carbon on the top of pistons after a few 1000 miles. Always have, always will.

[@OZARKSHDRIDERS]

Good job as always brother, yeah I watch DK Custom's all the time, and they showed a similar video of this catch can set up, I still haven't pulled the trigger on it yet but I think I'm just going to go ahead and do it, thanks again brother 👊🏼💯

[@GixxerFoo]

Anytime! It's a great setup to go with!

[@dwaynehollar6834]

I know right, I've been watching that shelf in several videos

[@ardyrides834]

Why does the crankcase need to be vented? A catch can doesn't vent the crankcase, because it's passive. What is the definition of an external breather? If a Twin Cam engine needs crankcase ventilation, something needs to suck air out of the crankcase. I tried the bypass as described by Doc Harley and, nothing is dripping out of the bypass hose. I never installed the catch can. What am I missing?

[@GixxerFoo]

The crank case has to be vented to prevent pressure build up, pulling crank case gases in to the air intake is a EPA thing. The EPA doesn't want crank case gases vented to atmosphere, they want it burned in the combustion chamber and ran through the cat converter. A catch can simply condenses the hot gases allowing moisture and oil vapor to settle to the bottom. The catch can greatly reduces the nasty oil vapor from coating the top of your pistons. Now bypassing the whole thing is blocking the head breathers for the crank case from entering the air intake and running it to a external filter or catch can. A filter will allow the crankcase to breathe and the oil vapor will be trapped in the filter, clean or replace the filter. In the case of the catch can you would simply empty the catch can. It doesn't require a vacuum to vent the crank case, the crank case will build pressure on its own and that pressure has to have a place to go. Blocking the head breather without venting to atmosphere will cause the oil to push past gaskets or even worse the rings.

[@roberttailer1464]

Stick that vent in your exhaust. No muss, no fuss

[@thekrutchinator]

Useless Harley engineers! Ruined the brand with their cost cutting measures

[@GixxerFoo]

The head breathers going back into the motor we have the EPA to thank for that. The same government arm trying to shut down motorsports period. RPM Act has got to pass and stop this nonsense.

[@thekrutchinator]

@@GixxerFoo thanks for the reply.. I'm Australian and wasn't aware of that.. I've still got a downer on some of the things Harley has done tho and you mention heaps of them! Like your channel and you give some great information...

[@billgonzales8978]

i just ride my old harley, yes it leaks, but it still runs 1984 starter went out so i just kick start it now glad it came with kick and electric start over 100,000 miles on it

[@GixxerFoo]

I do miss the kick starter days!

[@johncartwright1139]

DK custom has the best system

[@glickmpb]

Add it to the list of all the crap that needs to be replaced. This is why Harley is dying.

[@davedubeau9124]

I installed a Trask CheckM8. Problem solved

[@GixxerFoo]

Trask has got that crank case pressure issue figured out on these M8's.

[@paparalph4]

I have an 04 Heritage carbureted. Instead of a catch can I installed a beveled copper tube at the end of the hose and hose clamped the tube to the lower exhaust pipe. No noticeable smoke or dripping.

[@randomusernumber1]

Oh if only there was a way to avoid this problem from the start . What do you mean every other motorcicle manufacturer has figured it out . This is just one of the reassons that Harley has been on the edge of bancrupci for the last 30 years ,get with the times you air cooled, pushrod drven , no power making , oil guzzling , dinosaurs .

[@GixxerFoo]

They are fun to ride and the power comes on so early, I used to hate Harleys. I finally got talked into riding a Dyna with a 128 conversion, it's like a V8 muscle car out of the hole. Now granted after mid range a overhead cam motor is gonna over take it.

[@randomusernumber1]

@@GixxerFoo yeah but they dont make it like that out of the factory . and it still has terrible gas millage and al the other Harley issues which Harley grandpas describe as "Features"

[@GixxerFoo]

I'm not a huge fan of Harley's marketing structure where you pay more for the bike and then they have performance parts available. They have premium parts and finishes, but the engines do have their issues. Even the solid Evo has inner cam bearings concerns, but that's only on high mile bikes when you get over 40k.

[@josevalencia5145]

Good stuff. I run the DK customs EBS stage 4 catch can. This actually helped me notice how badly my engine was sumping. Since so much oil kept filling up in my can, I wondered why? Turns out excessive run out was causing sumping and blow by... So, if you're finding the catch can is filling up too quick or your EBS filter is saturated too fast, then you might have a bad flywheel. Anywho, good vid. 👍🏽🤙🏽

[@GixxerFoo]

That's a great point! Thank you for sharing that! Did you get your motor lined out after that?

[@blackvettespeeder]

I have K&N intakes on 5 of my Harley’s, trying to figure out how to set it up for a catch can without having to replace the whole thing, I don’t want anything getting sucked into the cylinder, can’t find anything on KZbin with K&N mods for a catch can, if anyone has any ideas let me know, Great video, you always have great context

[@garybaldwin1061]

I've done catch can installs on DI cars. It was pretty straight forward. You make it sound complicated. I would just vent to atmosphere since the amount is so small. I dont see why a different tune would be needed. Again the amount is so small. Airplane engines (lycoming and Continental) all vent to atmosphere. Over filling oil doesn't help...keep oil mid range on dip stick.

[@GixxerFoo]

It's not hard to do, it's just harder to on a bike while being able to hide it and make it look clean.

[@jeffreyengle2762]

2 years later…… screw the EPA😂

[@dongreer9082]

Awesome info but what the hell is going on with that shelf!!!!?

[@steph6934]

I really wonder why the air coming out of the breathers would be oxygen depleted since it's not coming from the combustion chambers but the crankcase and head. I get it is saturated with oil wich is bad, but my understanding is that this air is coming in and out every turn of the engine right?! Anyway, I'm looking into this for my 96CI Harley. Many thanks for all the informative videos you post.

[@chrisdawson8252]

Not sure if I get it. Combustion happens above the pistons and below the heads. That's your "combustion chamber" right? Where does the vented air come from into the breather bolts? Air goes in through the air filter and throttle body. Fuel goes in through injectors, sparks cause combustion. Do the breathers vent air after the exhaust stroke or intake stroke? And it's coming from the crank case? So that's under the pistons where no combustion takes place. I think I get it now.

[@Nerdonharleys]

Sounds good to me. Thanks for posting

[@jmac6242]

Thanks Gixer, always enjoy Your Vids...About this problem, "BLOCKHEAD" has a video for the DIY Guy, "Harley Blow By Problem Solved for $12 Explained" just as info...

[@GixxerFoo]

Thank you! I really appreciate it! I don't know if you saw his Sportster videos where he did the Hammer kit and ended up around 110 horse with the high dollar HPI throttle body on the 120hp kit. I kept saying it's the pipe he is using, swap that out for the magna flow two into one and it will make that 10 horse swing!

[@chadzupfer8005]

Great video always good info from you keep it up. Thanks