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

[@asquared7861]

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

[@rogermcwilliams6302]

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

[@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!

[@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

[@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.

[@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.

[@hollywoodboggie]

Gixxer a big shout out to you for all your advice. Just installed DK Customs breather bolt back plate and 606 air filter back plate and filter. Coupled with a Sifton Air Cleaner Breathing Kit and the result is BOSS! It works great, my dyno numbers remain solid and the overall appearance is one of a factory finish rather than a "Home Fix It" look. I admire those who have the talent and ingenuity to create the breather fix devices but wanted to keep the solid factory appearance. The two Sifton filter catches are directly attached to the banjo fittings which have extended stalks on which the filters fit. Finished in a high polished look the finished product is attractive as it is beneficial.

[@GixxerFoo]

Thank you, I appreciate it! That is awesome to hear! A lot of people pick up a couple extra horse on the dyno at the big end rerouting the breather system. You'll have a much cleaner top end going forward now!

[@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.

[@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.

[@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

[@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.

[@jeffreycarroll5920]

Put a DK Customs external breather with catch can on my 19 Electra glide A month ago. Man what a difference! Felt like the engine woke up! Very noticeable in power. No retune required.

[@GixxerFoo]

Very cool! Those catch cans make a difference, Hammer performance testing their Sportster engines were picking up a couple horsepower on top using catch cans and external breathers.

[@pb68slab18]

The crankcases internal air volume changes greatly when those 2 big pistons go to their TDC and BDC position in unison. No problem back in the Panhead days before electric starters came along in 1965. The engines internal rotary breather valve opened and the hot air vented into the tin primary chain cover. Oil in the vented air helped lube the primary chain, and was deposited back to the Earth from where it came. Same system was made to work with the electric start and rigid cast aluminum primary. But now the pump sucked that oil (and clutch/steel particles) back into the engine and oil tank. And keep in mind, this system was designed for the 61cu.in. or 1000cc Knucklehead. It worked fine. But as displacement grew to 74, and then 80 cu.in., or beyond, a new system was needed! I remember when the Twin Cam came out. There was a quote of one of the design engineers working on the vent/breather system who said he wanted to dig up William S. Harley and ask him what to do. My old bikes run a hose out the back hole in the cases with filter tucked up underneath. I've seen motors that did not run any sort of filter, just a hose almost dragging on the ground, and found lots of road dirt, sand, small stones, etc that got sucked up. These generally stay in the breather passage if too big to go thru the holes in the steel breather drum screen, or slots on the later plastic drums. If the breather drum wore into the case journal like many did, it could develop 'blow-by' and blow oil mist on the rear tire. It was common back in the day if you built a stroker, ya took the screen out of the breather drum. That was a bad move for the reason mentioned above. My '97 Evo headbreather has the SE crossover tube that came with a Stage II kit and a hose to a vent filter. .

[@dwaynehollar6834]

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

[@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.

[@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

[@leonardstanford1877]

I had a 1996 bagger that I made a catch can for it fit under the right side cover had a breather on top inside I had a baffle to separate air from the oil in the bottom It had a fitting that I attached a hose to & then I drilled the oil spout & attached the hose from the catch can to let the oil run back to the oil tank ! It worked excellent ! But like you said it takes some engineering to make it happen ! Good video ! ***** stars !

[@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.

[@bmp72]

I had a catch can on my moto guzzi 20 years ago... I duct taped a half a liter beer can to the frame and ran the hose in it. I never emptied it...occasionally on shutdown it would gurgle from the can. That bike was my all time favorite, but I had to sell it when I moved from Holland to Switzerland...

[@GixxerFoo]

That's awesome, l love hearing about catch can setups like that. Nothing wrong with it if it works, that's all that matters!

[@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.

[@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

[@michaelmorgan5714]

Years ago before all the complications I used BG44K in my 78 shovel head. One friend had an early bore scope so we checked the pistons before and after. Made one hell of a difference, so I followed the directions and kept it up once a year . Around 38-40 thousand miles I rebuilt the top end and the head was supper clean though it still needed grinding and new springs cam etc.I'm no motorcycle mechanic but I had some great friends still alive back then. I still have a V-rod and a Pan head. stepson has a twin cam. Good video Mike from Maryland

[@GixxerFoo]

Thank you! That's awesome you've got the best of both worlds in your garage!

[@michaelmorgan5714]

@@GixxerFoo Thanks but I sold the shovel head 30 years ago I do have a 65 pan head I put on a rigid frame but it stays in the living room. So between the V-rods, Sportster and pan head Yes We are fortunate.

[@stevechoi7837]

I just got a vrod. I notices it came with external breather but on rear engine only. How would you advice to install front breather?

[@leewarry8641]

In the old days we would take air filter elements out & use a puff pack to just puff a fine spray of wetter past carb & you could see the smoke come out the exhaust as the watter vaporize on piston & lift carbon out exhaust.

[@gregoryranlett7868]

Hello Gixxer, HPI (Horsepower, Inc.) offers their V2 Air Cleaner that flows 428 CF per minute of air and this will satisfy the breathing requirements any build! They also offer a EBS that goes with the air cleaner that is really slick! The price is reasonable for both items.

[@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

[@octavioquilichini874]

I too have a K&N air intake system on a 103 engine (fuel injected). The system has integrated cylinders or cavities where the actual breather bolts reside, the filter element plugs the outer side of these cavities, leaving no space for gases to escape yes they will avoid oily going to the filter but what about the hot gases! Should I drill small holes or did K&N design this on purpose, might this be detrimental to the engine?

[@paparalph4]

I have an 04 heritage 88 carbureted. I ran an external but simplified it. I put rubber plugs into the back of the filter, kept the original breather bolts coming out of the heads. Cut the rubber "S" tube that are on those bolts in half, put in a copper tube inside it and ran rubber fuel line into the copper tube and to a "T" connecter doing the same with the other head, then ran a line from the "T" out of the air cleaner box down the front frame to another 3" copper tube plugged into that. Bent it 90 degrees and did a 1/2" bevel on the very end but leaving a 32nd in opening at the end of the copper tube, hose clamped it to the front header pipe by my floor board. Figure, burn it after combustion instead of at combustion. That 32 opening keeps from any build up of oil. Been running it two years and only have a one inch residue mark on the pipe, no drips or smoke. No catch can to change out, I did that at first and didn't like it.

[@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

[@toddaod295]

Mine looks identical the chrome backplate you showed. Tubes from the breather bolts to a tee. I drilled the backplate to accommodate a rubber grommet so the tee fits very tight. Ran tubing straight down between the pushrods and forward down below the oil cooler. Very clean and discreet. All parts from ACE hardware. About 12 bucks I think. Did it 5 months ago and have not seen anything liquid out of it

[@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.

[@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.

[@mrnonpc9885]

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

[@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.

[@timconnors550]

I bought an external catchcan with breather from Mitsubishi its a pcv valve eliminator for Mitsubishi drift cars. A little fuel hose a brass t connector and a home made brac ket

[@paulsmale5436]

Just fitted a system to my harley heavy breather, have to say particular breather is well suited to the job. Bought all the parts DK lists off ebay and shaved £100 off their prices, used black braided hose and black anodised alloy hose end finishers, sprayed the T piece black. Blocked the tiny vomit vent holes with an inch of Gorilla silicon sealant. My only advice is ensure your thread tap is long enough to clear any potential obstruction or use an adjustable wrench end on ; ) Even though the AIT sensor is behind the butterfly in the fuel tract, meaning fuel cleans it on later model bikes, the thing will still occassionally get vomit from the head breathers on it and cause random slow rpm drop, or low speed engine cutoff. So not just a decrease in power and carbon build up.

[@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

[@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.

[@keeto56]

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

[@andrewstromfeld312]

When I had my 2000 LS2 V6 Saturn I would get the Bilstein oil flush, and induction service and the car ran great!

[@GixxerFoo]

Keeping the engine flushed out and the intake tract clean does wonders, just like on cars you gotta clean that throttle body out every now and again. That makes a huge difference!

[@HeyLookItsSmith]

On the M8 and Twin Cam, Trask Performance makes a setup just for this. It’s $150 but everything you need is there easy to install.

[@GixxerFoo]

Yes those vented trans covers are awesome for the M8's!

[@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.

[@SgtBFGunner]

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

[@hdlstns]

I currently have both a D&K external breather kit - drilled and tapped my SE stage one backing plate, AND a Feuling vented dipstick installed in my high performance custom 107" motor. I still get more than a little oil coming out of the D&K that I have routed to a K&N filter below my intake, but usually only when I am running the motor pretty hard in the hills and curves, or running near 3000 rpms on the highway for an extended period of time. This is really aggravating. I have just ordered a TRASK intake and they do offer a head breather bypass option for additional money that replaces the bushings between the backing plate and the heads. I think I'll be running this time in an upward direction so as the oil mist condenses, the oil will drip back into the heads instead of on to my camchest cover...

[@GixxerFoo]

Damn yeah those M8's are a pain with the oil from breathers. Hopefully that new setup will help, sounds like you've done everything right to combat it.

[@RayfordRaySiegel]

I'm glad that I saw this video. I had come across a couple videos, by DK Customs, about external breather systems, and I was thinking about eventually getting one. I was thinking that it sucks that carbon is already on my pistons, and I'm just stuck with it. Now, I know that isn't the case. I also didn't know that Hammer Performance has an external breather system for Sportsters. I'll definitely be checking into that, for mine. I appreciate all the information. Thanks

[@davidroberts8410]

Take the air cleaner off and mix rubbing alcohol and water in a spray bottle. Start the engine and let it warm up and start spraying the water mix into the throttle body/carb. You may have to give it some throttle but as soon as it hits the insides of the engine look at all the black shit coming out the pipes lol. Nasty stench too. Then let it cool off and look thru the spark plug holes with a small borescope and the tops of pistons will be gleaming clean.

[@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.

[@mitch2519]

Your more recent video about the benefit of a vented dipstick is a good footnote to this video.

[@GixxerFoo]

So far the sumping issue is mainly on the M8 but any Harley engine can have it happen. The M8 just has a serious lack of crankcase ventilation with the head breathers. Vented dipsticks would sure help on any Harley engine for sure though too.

[@mitch2519]

@@GixxerFoo I am doubling up. I ordered the Freuling vented dipstick, and I am also routing 1/4 inch tubing from the breather bolts on my SE Ventilator down to a t-fitting, then down a 3/8 inch line to a Uni crankcase breather filter that I will mount under the bike. I am doing all I can to keep that crap off of the top of the pistons.

[@jjbigwheel]

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

[@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!

[@theodavies8754]

Back again, with the cv carb the biggest issue seems to be pulling oily air into the air jets. The result is restricted air supply to the primary which goes rich and emulsion tube gumming up which causes sneezing getting on the throttle,worse cold running. Spray some carb cleaner into the two small holes with brass jets to restore the mixture rather than constant twiddling the idle air screw. It's an easy fix but doesn't stay fixed for more than 1k miles. Standard airbox and exhaust tends to spit enough fuel mix into the airbox to wash it through but who leaves them on?

[@Hodado]

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

[@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

[@joescott803]

I just did mine when I swapped my tc to mikuni. It was simple and cost twenty bucks maybe. Y brass fitting and a little filter with some 1/4” hose. It actually seems to run better too

[@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 👍

[@dieseljuice3]

Just ordered a DK Custom products External Breather System for my 2012 Heritage with 16000 miles.

[@GixxerFoo]

That's a great system!

[@slickrick4202]

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

[@andrewwiltse8882]

I don’t own a HD and I don’t plan on getting one but I really enjoy watching your channel. I’ve always wondered why HD does what they do and you explain things very well. ✌️

[@GixxerFoo]

Thanks for watching! A lot of the principles with Harley's still apply to any bike, just like routing your crankcase breather to atmosphere.

[@nunoaraujo7381]

My bike started to fail on the front cylinder... I discovered that the spark plug was failing. Even new ones. It mostly happened after a short break on a trip. After doing an external oil breather, the engine started working perfectly and never had any problems again.

[@pablo6305]

I been thinking this for years. I should. On my 2010 screaming eagle. Should i plug holes in side of carb from the breather? after i put t to air filter.

[@GixxerFoo]

As long as it is vented to atmosphere but don't plug the holes and not let the crankcase breathe.

[@alanbobowicz141]

The Trask intake has an external breather capability. Neat and clean.

[@GixxerFoo]

That external breather is the way to go!

[@unclemikeb]

I was amazed when I took a hard look at the set up on my 2000 wide glide. I had asked for the screaming eagle air filter before it left the dealer. Lo and behold, that included a vent system that has a drain tube routed down behind the engine. It does not have a catch can, it just vents. LOL My local Harley shop told me that was standard Screaming Eagle with that year. I looked at their website but could not find it. Maybe they had to discontinue it due to some EPA rules?

[@GixxerFoo]

Yeah EPA cracked down on that, being a 2000 model that bike and all parts made for it would of been exempt from the new regulation. Sadly I don't know for certain how long that is going to last the way things are going, I'm sure eventually they will do away with the grandfathering in.

[@unclemikeb]

@@GixxerFoo Maybe I should delete this so "they" won't know? LOL Pizzonit. Although there is a set up where a guy routed hoses down under the filter element and back up near the top where he added gasoline filters to trap the oil vapors. That should dramatically cut down on what goes into the engine. Probably need to change those every 5,000 just like the engine oil. Another tip would be to leave the oil level halfway between full and add so as to leave more room in the crankcase.

[@jocrp6]

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

[@jiismo]

For the carbon...way back when I went to MC school they taught us to mist water in the intake using a spray bottle. the water is superheated and gets in the carbon and expands and breaks it up. I've done this many times. seems like a similar non chemical version of the topend cleaners mentioned.

[@GixxerFoo]

That works really well, it's good trick to use.

[@jsasu.3]

Thanks EPA! This is going on in just about everything with a motor these days. Diesel mechanic showed me the piston from a yard truck with 50k miles. 100% Horrible what this does to an engine. Bypass and catch can it ASAP!!

[@motorcitymadman146]

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

[@bigdaddy5948]

I got my external breather kit a Lowes.

[@GixxerFoo]

Nothing wrong with that at all, it's pretty easy to make your own. That's basically what the aftermarket units are anyhow.

[@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?

[@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.

[@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”)

[@dongreer9082]

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

[@Jeff-tt4yt]

I’ve fought with the idea of an external breather for years but finally put one on a 2016 103. I know there’s a lot of controversy about installing one, but if you’ve ever seen what’s in the breather or catch. Can you have to wonder how that could possibly be good for the motor. Thanks Foo another good one.

[@GixxerFoo]

Anytime! I run a catch can on all my bikes, even the car and truck. You almost have to these days with any direct injected vehicle, you're asking for trouble on DI if you don't

[@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!

[@peteryeanacopolis2037]

After looking into the EBS systems and watching your video I went with the DK Customs system with the catch can hanging under the breather, (why pay for a piece of billet and not accent it) for easy access. I opted for the steel braided line and shiny clamps but since they were hard to work with I just got some 3/8 gas line and used zip ties instead of clamps since there’s no pressure on the lines. They only breathe. Took the bike for a ride to make sure I had everything tight and wasn’t looking for a power gain but I did notice a little bit better response in the throttle, again, wasn’t looking for it so I ruled out the “placebo “ theory.

[@GixxerFoo]

Hammer performance tested it on their dyno back to back with their shop bike. Routing the crankcase breather externally netted a couple horsepower on the big end!

[@peteryeanacopolis2037]

@@GixxerFoo thanks! Now I know it wasn’t me👍

[@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.

[@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!

[@jamessouthworth1699]

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

[@weaverlarry6]

I'm looking at that shelf and I'm impressed. How far down it will go before it snaps

[@fastone136]

i've heard of just a spray mist of water into the throat body as revving at same time breaks up the carbon as well.

[@GixxerFoo]

It won't like it but it will knock the carbon off.

[@CharlesWillisBonsai]

Seen the same thing done but with seafoam

[@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!

[@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!!.

[@JohnJones-op8uf]

I run a DK catch can on my 2013 Softail. Great products

[@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?

[@bradduffield9603]

Great information. Thanks for the options available.

[@hatfieldmccoy2359]

I wish I would have had KZbin in 2007, I wouldn’t have never went to Motorcycle Mechanics Institute in Orlando Florida. Enjoy watching your videos! Keep up the good work!

[@GixxerFoo]

Lol KZbin really isn't a replacement for some quality training like that. Years ago MMI was hanging around the old mechanics lift until he finally told you hand him something lol.

[@drumsnbass]

How much are you spraying in there for overnight cleaning?

[@colesnorris]

I routed my breather lines upward just under the fuel tank, then back down under the carb to the catch breather. I've found that the oil mist goes back to the heads about 90% more, and out of the catch breather. Would post a picture if I could.

[@GixxerFoo]

Thanks for sharing! That's a really good tip!

[@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!

[@joemaccrory8121]

I added the Feuling dip stick breather for my 114 M8. I'm also going to add the Trask Assult air breather with the external breather option. Not sure if running both is recommended so i'll have to look into that before i add the trask component.

[@GixxerFoo]

There's no issue at all running both and it's just good insurance on a M8.

[@alanbobowicz141]

Trask “checkM8” transmission cover vent is the way to go. Nick Trask has a 1:00 video on it, as well as an installation video by Moots.

[@timdavis8154]

I ordered a DK catch can.

[@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.

[@richardweidman2298]

Horsepower inc VO2 air cleaner and there tunnel ram have external breather hoses

[@IrvingtonArms]

When I got to my first maint on my 2010 was blow away at the oil inside my air cleaner. I always wondered where the hell the oil drip was coming from. Routed it to under the bike w/ a filter and chazam great air filter life!

[@GixxerFoo]

That makes a big difference in keeping the top end clean too!

[@cynthiaayers7696]

Same thing with the older cars, they had a Blow by pipe on the valve cover.

[@GixxerFoo]

It worked great till the EPA got involved and wanted it reburned in the combustion chamber.

[@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.

[@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

[@234Jumbo1]

Horsepower Inc. has an external breathersystem vor their Aircleaner as well👍🏻

[@GixxerFoo]

Yes! I found them after the video, I am looking at getting one of those!

[@tonyl8314]

You stated that one may possibly have to retune the engine if running an external breather sustem as the bike was tuned with the head gases going back into the engine. Does putting an external breather on it make it run leaner or richer?

[@fps636]

Thanks. I like the spray in the cly method then change oil next day.

[@GixxerFoo]

That's way I like to do it, it works really well!

[@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.