This is a prototype setup Ive recently put together.
The intake bolts do not have a hole on the shaft within the intake plate, so nothing can get into the intake, throttle body, intake manifold or combustion chambers.
The center port on the can is for pulling vacuum, and the vac supply comes from the unused nipple on top of the throttle body, which is behind the throttle plate, where any PCV vac source should be, vs in front of the plate on a Harley OE setup. Im using an air speed control valve, and have the vacuum adusted to 5 inches.
This can will catch the unburned fuel, water vapor and oil and other crud, and the extra vacuum will be helping to not only open the umbrellas earlier, it will also help evacuate the fumes and crud more, whilst also intruducing more crank case vacuum by the time the umbrellas slap shut again, which will aid ring seal and lower the blowby, among other things.
Im currently desiging different breather bolt setups so this can be used on just about any intake, and Ive since redesigned the coil pack mounting bracket to bring the can much closer to the coil.
So far, all Im getting is a bit of water, which means this is definitely improving ring seal and oil control, and reducing blowby bigtime, as usually, there would be oil, unburned fuel and the white, nasty slag that you get into the intake tract. Im working on breather bolt setups that will allow this system to be used on almost any intake as well.

 

If you have that much blow-by that you need that spider hanging off the side of your bike, you have bigger issues that need attention.

 

Every motor gets a bit of blowby past the rings, which is why we get all the crud in our intakes with the OE setup, made up of water vapor, oil, white slaggy junk, and unburned fuel. This system will not only improve ring seal by placing the crank case under additional vaccum, it keeps the intake tract and piston tops clean too, and less blowby means cleaner oil and better oil life as well.

 

I'm confued. How does ring blow by gunk up the intake? How does creating a vacuum in the crankcase reduce blow by? How if there was blow by the rings, would that even suck more last the ring? I’m confused.

 

Blowby introduces unburned fuel and oil vapor and pressure into the crank case past the rings. The pressure causes the umbrellas to open and puke out some of the pressure, along with whatever gets past the filters beneath the umbrellas, and the slight vacuum created by the tubes on the intake facing the throttle plate aid in the evacuation and also pulls the junk into the intake and into the combustion chambers to be reburned to satisfy the EPA, but also causes an intake tract coated in oil and junk and piston tops covered in carbon.
Blowby can also go past the rings on the down stroke due to a pressurized crank case. One of the problems associated with the early M8s was wet sumping, due to the pressure aerating the oil, and the crank case breathing through the pinion bearing on the oil pump side.
Harley's solution was to produce a backing plate with a seal to prevent the case from breathing through the bearing on later models.
The added vaccum from my system, as said, will let the umbrellas open sooner, and will not only forcefully evacuate crank case pressure, it will also cause the case to be put under more vacuum when the umbrellas slap shut, which will force the low tension rings against the cylinder walls to create a better seal, reduce aeration of the oil and thereby help prevent wet sumping and cause less oil to come out of the breathers since misting will be lessened. Oil should stay cleaner throughout the service interval as well, due to less crap getting past the rings, and better evacuation of the crank case gasses. The can itself filters the crap out of the air so it doesnt get into the intake tract at all. So, in short, you get to keep a clean intake whilst retaining vacuum assist on the crank case. Here is a photo of the improved bracket I recently made to mount the can closer to the coil.

 

If you skip to the 1:36 ish mark in this video, your see what Baxters Garage has to say about crank case vacuum. Not many get into this stuff and it is a very overlooked, integral part of engine performance.

 

This is pretty much the same kind of device that Ron's Workshop came up with.
I'm staying with the trask check M8 since it has a reed valve.

 

Interesting. Regarding the trask setup, as much as I respect them as innovators and makers of great forced induction kits, I dont care for the transmission cover vent, since with the OE setup, the gunk has somewhere to go, even if its in your intake tract and burning in your combustion chambers. Venting to atmosphere with no vacuum aslo gets some of it out at least, at the cost of minimal crank case vacuum and a mess. But the vent to the trans cover, IF youve plugged your oe ports that allow the gunk to be slightly vacuumed into the intake, will keep the stuff in your oil, as it is just going to come out of the umbrellas, make its way to the top cover, and go right back into the oil supply, and therefore, only build up in your oil and dilute the oil with water and fuel.

 

I do intend to do much testing on my system. Seems the dyno would be the best way to prove whether or not better ring seal is being achieved. Can be tested in OE, atmosphere vent and my system configuration.

 

Install the Trask Check M8 transmission top cover. It will pretty much eliminate anything going into the air cleaner while still allowing a slight vacuum in the crankcase. And you want that vacuum to assist in venting the vapors out. Catch cans keep stuff out of the intake but they do nothing to help remove the nasty stuff out of your engine.

I've run one for four years now. As long as the vapors get out of your engine before it cools down and condenses back into fuel and water there is no oil contamination. Pressure buildup from the pistons moving downward and any blowby pushes vapors out of the Trask unit. Since it has a one-way reed valve nothing can get drawn back in, You also still have the vacuum from the breather tubes in the air cleaner supplying some vacuum as well. But the Trask unit takes care of the vast majority of the vapors.