Harley M8 Vented Transmission Top Cover instead of Fueling Vented Dipstick. life pranks 

Adding external breathers doesnt loose ur vacuum. It just keeps oil vapor from going in ur intake. The breathers have umbrella valves.

Great footage! I’m gonna do the same thing. Yesterday i got the zippers redshift 468 cam in my 107 roadking special, and it’s come alive bigtime! 🙌 so a little more venting is a good thing.. i already made an external breather with catch-can on my S&S Stealth air intake… no oil in my intake anymore. Up to the garage to take this on. Have a good one brother and thanks! Greetz from The Netherlands, yes the land of windmills, wooden shoes and gouda cheese 🇳🇱 🧀

Exactly. I did them both. A1 Ventilator and a catch can. Remember, you don't have to change out the butterfly valves to run a catch can. Remember what Kevin said, pros & cons. I feel what I have done, is working for my bike. 500+ miles, no problems. I run my oil level 8 ounces low, 5 dots down from full.

Great video! helps alot to understand sumping, blowby and what to do about it! Thanks!! keep up the good work. Greetz from a M8 Street/roadglide fan from Holland (land of the clumps haha)

For a little more discreet finish, try to find a bulk head 90 for the top. You also need a one way valve in the system.

A one way check valve in your hose somewhere would be a good step to add. Good video, thanks

doc Harley recommends not venting into the intake ......just sayin . i do like the transmission vent though

External breather kits work perfectly fine! It also increases the amount of clean cool air into the cylinders! Rather than hot oil and mist!

That’s funny. Kevin built my Skunkworks motor and he vented the air breather to the atmosphere. The fueling dipstick on the bike and the trans vent.

Did you get any kind of mess inside ur side cover from where you ran it or did the filter catch anything that may have come out?

Hello my friend I have a question I have a 2000 road King I'm putting S&S 124 motor in ( twin cam). Can I vent the top of the trans cover the same over the air bypass from the engine to the oil tank to keep vacuum pressure? And is this all that is necessary without bothering with a dipstick vent or external breather? Would this work the same for a twin cam as it would for the M8's?

Very informative, I have seen the videos you referenced but putting them all together with your ingenuity turned the light bulb on. I have the TRASK M8 & Venting Heads on my Fat Boy. This Road Glide I got was spitting oil from front breather bolt saturating the Breather filter. I tightened the bolt which stopped the leak, but where does the excess oil go if it’s not being pissed out the breather bolt? Do you think tightening the forward breather bolt improved crank case vacuum? OBTW, your videos are fearless. ET’1(SS/SW/MTS) US Navy, Ret. 2020 Fat Boy 2021 Road Glide

Ok so does the hose have to be that long ? And is this equivalent to the breather / dipstick mod ?

Is the standard ventilation on the current m8 engines adequate?

I have an '08 Road Glide with 110,000 miles on it. It has a highly modified Twin Cam 107 with 11.3 static CR, Tman 590s, highly ported 110 heads, and custom "pop up" Mahle pistons. It had made 128 lb/ft and 126 hp to the rear wheel. It now has over 40,000 miles on it and is still going strong. It has been externally vented at the breathers for almost all of those 40,000 miles. It does not consume oil. So I disagree on this one.

Also, how did your fat clutch rod fix work. Did it solve the trans oil transfer problem?

The Trask version, while expensive, does have a one way reed valve in the cover. It releases pressure and then creates a vacuum. Now I don’t know how crucial that is but it seems to be well thought out. The reason why it’s so expensive is because it has a relatively low production rate. The more volume you sell, the more inexpensive you can make it.

Would that Ying yang the pressures from one chamber to the other? U would loose any negative pressure for the rings too seal good

25:27 That's exactly where I placed my vent filter from the TRASK Vented Transmission Top Cover. On my Low Rider ST

what size bit to get the bolts out?

Do the vent from the breather bolts! And than run your bottom line to the trans case at the left side... closer to the exhaust when you take it off there is 3 chambers! Transmission case and trans vent an than there is a crankcase vent... almost like Harley was going to vent but had problems with epa! Do the external breather bolts than run your hose to the crankcase! Thus getting rid of blowby from getting into cylinders while maintaining vacuum! Bam!

Lucky you were, I noticed my 2021 model has a cast Al cover too. Have you checked to see if, and how much oil misting you are getting behind your cover and in the frame since? If you listen to Baxter's comments closely, he implies a internal vacuum might be beneficial for the rings to seal more properly, and there for you might want to add a PVC or pressure check valve to your 1/4 hose line.

What is the problem to put the tube and catch can on Vented stick 🤔?

Does this void warranty

You didn’t put a pressure valve in? You are not creating a vacuum for the sealing of bottom piston rings. Did you find higher oil consumption?

old gm engines would vent directly to atmosphere with air filters directly on the valve covers you don't need a vacuum although it would be beneficial to have one having no pressure or vacuum will not damage you engine having pressure in your crankcase can cause damage so externally vented breathers will not harm your engine

Unless your running a super modified HD, then yes a vacuum pump is a must to help seal the beast. But ona daily rider or mildly modified HD, a catch can will do just fine for crank case evacuation.

How about a 90 degree out of the back like the middle compartment has but laying down angles outwards

Is that a one way check valve?

on pans, shovels and evos, you had a rotary valve that was used to create vacuum in the crank case. With these vents on M8 wouldn't it be better to run them to a vacuum source like manifold, or the collector on 2into1 pipes? A vacuum will allow the piston rings to seal better and less loss from moving crankcase air around. I haven't torn into an M8 so don't know the oiling system like the old stuff.

Then what about venting the air cleaner but loop it without oil going back into the throttle body?

There is another video where someone takes the same approach of doing themselves but also incorporated the one way reed valve quality of the trask cover by installing a one way valve in line with the filtered line coming off of the nipple that is installed in the tranny cover. I like that idea because it maintains the vacuum that is necessary to help the rings seal and to potentially squash the foaming effect of higher revs on the engine for extended periods

I am still confused how an External Breather attached to the head bolts disrupts the vacuum state, Those head bolts simply blow out hot oily mist from any blow by back into the intake to be burned up in the combustion chamber. Two little hoses that are pointing directly into the throttle body. Ricky HD said the same thing about vacuum in an older video, but I don't see how it's possible. Can you enlighten me ?

What size fitting?? 5/16??? 3/8???

I noticed you didn’t use a check valve? Why?

Why did you only use a small hole for the vent in the gasket? My softail has a completely different gasket that has the entire chamber open. I thought about cutting that small section out of the gasket on my road glide when I do this. Any thoughts?

Not sure I trust mechanical advice from a guy that is using a torx bit to remove a socket head fastener. It should be a 3/16" hex. Just saying.

Did you have a 1way valve to keep the vacuum like Baxter recommended

I added the Trask unit to my M8 and discontinued using my vented oil cap and have noticed a lot less oil in the Rinehart air cleaner and the engine feels better. I used to have a lot of oil dripping from the air cleaner now it's barely a drop after a few hundred miles and I'm usually running it hard.

Check valve ?

How did the location of your filter work? I was concerned about getting oil mist behind my side cover. I’m going to run my hose like you did but then take the filter to the bottom of my bike and towards the back Of my bike.

Can you use a 1/8 NPT Male to 1/4" Hose Barb 45° Degree Adapter Fitting Black or what size should you use?

I just did this mod last week with a check valve on my 2018 Street Glide. After riding this weekend I found a oil in the tailpipe, inside my air cleaner (Stock air cleaner from a 2020 Softail Lowrider , no mods,) and the breather is wet. The breather is by the back of my fender. There is oil dripping on my rear wheel and tire. Any idea why I lost 1/2 a quart of oil and made a mess of bike. I ride at high speeds at times, but before the mod was never had this problem. Any help would be appreciated.

I’m almost done with a diy vented top cover by using parts from Amazon I’m using a 1/4” bulkhead fitting so I’m only out 50$ usd I also got the cover off with only removing battery cover and other side cover because I have so many sockets and swivels and ratchets it only took 5 minutes to remove the cover

The reason you're getting oil all over is because you have to run the line higher than the intake

I vented my transmission top cover to intake with fuel filter in middle so vacuum is pulling from in the crankcase not above breather bolts to catch can 500miles later little puddle of very clear water in it before with just venting crankcase I would have oil after every ride bubble oil to now no bubbles in oil and oil level check now is two dots higher every time then before trans vent vacuum dots was 5 now showing seven dots no oil added for hole process

wheres the no return valve to avoid a free breather?

I vent the top and bottom have no problems . Epa is the problem sense 1993 👌

Where did that cute lil tool come from

Does the transmission vent the crankcase? I thought they were separated in Harleys.

Okay I have an M8 107 on a 2018 Road Glide Special. Had a lot of oil spraying out onto my side cover and saddle bag. Now I put a HPi Heavy Oil Breather so far no more oil. Why did this happen in first place?

I’d really like to see Kevin Baxters full video anyway that you can leave me a link?

I did the same thing except I put a one way check valve so the blowby escapes but it will still get vacuum couldn't hurt just want to stop most of the blowby going in throttle body

That "Feuling vented dipstick" , as well as the "Trask vented transmission cover" are equipped with one way valves , to achieve an "under -pressure" in the cranck case , which helps to prevent cavitation of the engine oil , which is one of the causes for that "sumping issue". The Feuling vented dipstick doesn't solve that much due to the too tiny inner diameter of that rubber hose . The Trask vented transmission cover is a better solution.

When will HD work out all these kinds of problems before releasing a new engine?

does this venting eliminate the need for a new pump and camplate?

What model of Harley are you doing this on?

After doing more research on these ideas, I have come to the conclusion that this video is taking the vent to a free breather. With the trask cover there is a reed valve that maintains a one way venting process keeping vacuum (IF there is any) and expelling any excess crank case pressure. In Kevin Baxters video in the last few seconds of his video he says "You almost have to do both" meaning venting the crank AND the heads where the breathers are, even after suggesting there is a possibility of vacuum at the air cleaner. Realistically I can't accept the idea where two small hoses sitting OUTSIDE of the throttle body where suction is going to take most of the air from the outside thru the air cleaner rather than to say to the air available, "Gee I think I will selectively pull air thru these tiny tubes that are VENTING pressure and oil mist instead of taking the vast majority of air from the environment thru the air filter to help maintain a vacuum"... Meanwhile the blow by gets shoved into the throttle body as it comes OUT of those breather tubes, to be mixed with fuel and air to make a lovely mixture that will certainly benefit the combustion chamber. Having researched the manifold vacuum qualities of engines I found that the smaller the engine the less vacuum there can be in some car engines. V-8's make a ton of manifold vacuum pressure, there is less in a six cylinder and barely any in a 4 cylinder in some cases. I have found videos showing vacuum in a lawnmower engine, but in the case of a v-twin due to the amount of blow by because of the rings and the weak oil pumps the v-twins make a shit ton more pressure than vacuum. For the most part the only way to make vacuum in a v-twin is to install a vacuum pump and mostly this is only done in racing applications or on drag bikes. Sooo. I wouldn't do what this guy does in this video. Here is something that was said by Dwayne at DK custom products. "There is in fact a sort of PCV system in place... Within your rocker boxes there are valves that meter crankcase pressure within the head breather system. Twin cam and sportster models call these umbrella valves I believe on the M8 they are just called head Breather Valves if you wish to look those up. The intake does not pull vacuum within the head breather system. Positive crankcase pressure is present here. The goal of a head breather system is to ensure only clean, oxygen rich air is in the intake. It doesn't alter or reduce crankcase pressure in any way. Think of it this way... in stock form, your head breather system has open ended tubes pointing into the intake. While there is a venturi in the air box or there is no suction here for the head breather hoses (think of a drinking straw). Those hoses are blowing the crankcase vapors into your air box/intake... An external breather system simply re-routes those hoses to the atmosphere. As a test you can do for yourself, attach hoses to your head breather system and briefly collect those hoses to a balloon. In about 20 seconds the balloon will grow to the size of a grapefruit with or without the trans vent. Keep in mind this is entirely outside of the air box (no vacuum). With a trans vent, the balloon attached to the head breather system may expand at a slightly slower rate but it will still expand and be filled. What is inside that balloon is oil vapor, condensation, crankcase gasses, etc... All of that displaced volume within the air box... This means less oxygen intake. Venting at the other end of the crankcase can reduce head breather pressure but can not, in any way, eliminate it. Will it reduce the head breather pressure enough to prevent liquid oil carry over? possibly. We have not tested any venting systems but it must be understood, they can only serve to reduce the volume that is passing thru the head breather system... not eliminate it. Every bike is different... some bikes pass up to 1 qrt of oil thru the head breather system within 1500 miles. Venting the crankcase on such a bike wouldn't make a noticeable difference in oil carry over here. Many bikes produce little to no oil carryover. The vent may be just enough to eliminate the oil carryover on those bikes. It is not a matter of other products failing to do what a head breather system does... It must be understood that the product you have, and the External breather systems we offer, serve different purposes. The trans and other venting systems claim to reduce or eliminate the oil carryover. I am sure that in all circumstances crankcase pressure is reduced and in some cases eliminated. if that is what you wish to achieve, those products are great. If you want to re-direct the head breather system from venting into the intake, you need an external breather system. I do understand this is a hot topic but this is something consider IF you are hoping to prevent oil feeding into the intake.... No one making a vent product that reduces crankcase pressure will guarantee you that no oil carryover will be present in the intake because is an impossible claim to make. With an External Breather system, there is not oil venting into the intake. This is not debatable. Ride Safe - Ride Free Dwayne The reality is after installing the catch can at the breather bolts on my 114, and after 3000 miles there is NOTHING in the catch can. It is as squeaky clean as when I installed it. When inspecting the catch can at the trask vent, there is what looks like Hot oil deposits in the can but the deposits are sticky and kind of dry. So I think the trask vent is working and taking care of any excessive crank pressure and made the venting bolt catch can redundant. I have become a supporter of the RU-vid videos that Kevin Baxter does since I have also decided to have him build my motor. He emphasized in a members only video that taking the breather bolts to a catch can, can take away some help for vacuum tho he also says it does not MAKE vacuum at the breather vent. But he also says the design harley came up with may not be ideal but it is not hurting anything unless the motor is sumping and when doing a leak down there is a lot of leakage. There are a number of vids that claim that the carbon buildup on M8 pistons is due to the blow by oil mist that comes out of the breather tubes. There are some reputable mechanics that say otherwise and that the build up comes from ethanol and NOT oil mist. So I have also concluded from my test that there is no oil mist and no reason to vent the breather tube outside. Another thing... UNLESS there is oil coming out of those tubes there is NO reason to vent them to atmosphere that I can come up with, and this has to do with the idea of the fart in the wind concept again. The tube is so small, and if you have something like a vent at the transmission or dipstick it is not likely that you would have anything bad coming out of the vent tube. It may not be as oxygen rich as the air coming into the intake thru the air filter, but it is such a tiny amount it may be minimal as far as depleted oxygen or bad air if it does in fact support vacuum when it comes to any side effects. For anyone who has done an air cleaner upgrade I can't see any real loss to combustion air when I look at the size of the hole in the tiny tube that comes out of the "teed" hoses that come together to vent in the single tube in my intake outside of the venturi. I personally haven't done the balloon test, but I have found WITH the catch can that there is no oil misting. I've since decided to listen to a mechanic that builds motors for a living and knows what the hell he is talking about. It will be interesting to see after the build if he leaves the breather tubes in place, but I kind of think after his discussion that he will find no reason to remove them if the motor is tight and AFTER he does a leak down test to make sure it is tight.

You didn’t spend over $300 for that Trask overpriced piece of aluminum. Luv it !

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Looks to me it will be pulling more on the head side now thus putting oil in your air cleaner…

Hi. The diameter of the breather base on the transmission cover Is 1/8 or 1/4?

OBTW, both bikes have plastic Transmission covers. HD will save a dime even if it compromises quality to customers.

I've never had an issue with the vent breather.

I’ve used the fueling vented dipstick on my m8 RK for almost a year with a 122 build and it has worked perfectly. Also Easy install. I recommend over venting the transmission cover.

You show the video from Baxter Garage saying the engine needs to be in a vacuum you vent your engine to the atmosphere. You have effectively removed all vacuum the engine creates with your DIY kit. The Trask cover has a reed valve to only maintain the vacuum.

U realize that the little black tube already on the cover is a breather tube lmfao😂😂

So why do you need an additional vent at the trans cover for the crankcase if there is already one at top that vents into the intake?? Anyone?

Only thing is.. he is the only one saying this about the breather.. what he says holds weight. But.. other side of the coin ia also true.. IDK?

There is no vacuum in the breather. Key word (Breather). if that were true the entire breather assembly would be a massive check valve! bad info on the vacuum/catch can

It's hard to pull a vacuum in a pressurized system, ..

Bikes is ultra limited 2017 m8 107

ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-726Bzh7F-2Y.html Kevin Baxters full video link

Have you noticed a difference yet?

This does seem the way to go. People that don’t have the issue I believe are not having them because it seems to only show up at higher RPMs and longer duration and Kevin mentions that. The dipstick method will work but not as well

The new trans top covers are plastic

I can't hear what you're saying. Get closer to the mike maybe?

So Harleys engineer don’t know what there doing sad

My M8 already has a vent on the transmission cover from the factory.

This guy is a hack. No vacuumed with a hole in the transmission lid. Heating a electric probe to make a hole 😵‍💫. You need a reed valve in your lid. Filthy bike. 🤡