A question about the crankcase breather filter...

Bedifferent

Old man on a bike
Joined
Dec 11, 2014
Messages
1,764
Location
Coldwater, MI
Ride
2015 Rocket 3 Touring
When I installed my RamAir last summer I never put on the crankcase breather filter supplied by RamAir. I originally planned to put a hole in the RamAir housing and then run a hose from the crankcase vent to the RamAir. Instead, I simply left the hose hook up that runs into the air filter box. I never removed the original filter from the air box to make room for storage.

Some have said this results in oil in the air filter box. I checked mine this year and it is as dry as a bone. I realize that with the original air intake system on any air or vapors would be scavenged out of the air box. The question is....As long as the crankcase vent still has a place to vent into the filter box, what is the need for me to bother putting the vent filter on or venting the crankcase in some other way? BTW...The only other thing I have contemplated doing is putting a piece of breathable filter foam in the bottom of the filter box.

Any thoughts?
 
yep.....the breather hole in the bottom of the filter box is very small isnt it?...if it gets a bit of crap in it it will block.
The wee triangular side panel on the right hand side by your leg is where you access the crankcase breather hose...its where the ramair filter is meant to go.
i put mine in there, when you take the hose off the breather and pull it out, you will find its an 's' shape hose.
I cut mine thru the middle so it is now shaped in an 'L' shape. I put the short end over the crankcase breather lug and had the long piece pointing out toward me...then i put the filter in that. Now the filter sits right there so you can get at it to clean it..it makes a difficult task into an easy one.
Hope this helps.
 
yep.....the breather hole in the bottom of the filter box is very small isnt it?...if it gets a bit of crap in it it will block.
The wee triangular side panel on the right hand side by your leg is where you access the crankcase breather hose...its where the ramair filter is meant to go.
i put mine in there, when you take the hose off the breather and pull it out, you will find its an 's' shape hose.
I cut mine thru the middle so it is now shaped in an 'L' shape. I put the short end over the crankcase breather lug and had the long piece pointing out toward me...then i put the filter in that. Now the filter sits right there so you can get at it to clean it..it makes a difficult task into an easy one.
Hope this helps.

Putting a K&N or the RamAir filter on as supplied would not be a problem. Allowing for easy access would make it easier to service. I just felt since it was venting in the air box which was located further up and out of the weather why not use it. My thought on a small piece of breathable foam on the bottom of the air box was just for the reason you mentioned...so nothing would make its way into the small opening in the bottom of the box. Actually that could be enlarged. There also has been speculation here on the forum that the add on filter might be contributing to additional crankcase pressure resulting in the common valve cover bulging, failure and leaking.
 
There also has been speculation here on the forum that the add on filter might be contributing to additional crankcase pressure resulting in the common valve cover bulging, failure and leaking.
Personally i dont think there would be any added pressure but if there was...which is the easiest, least resistant route for that pressure to go?..the oil filler cap. Its just a push in cap right? so it would blow out if pressure was building behind it.
 
Personally i dont think there would be any added pressure but if there was...which is the easiest, least resistant route for that pressure to go?..the oil filler cap. Its just a push in cap right? so it would blow out if pressure was building behind it.

Actually, several people have had that happen. I guess it was my understanding that the tank was a reservoir for the oil being pumped around the engine and up from the sump...I didn’t think it was tied “directly” to any pressure generated in the crankcase.
 
Actually, several people have had that happen. I guess it was my understanding that the tank was a reservoir for the oil being pumped around the engine and up from the sump...I didn’t think it was tied “directly” to any pressure generated in the crankcase.
The oil tank is vented from the top to the crankcase right above the clutch basket. That black hose is not there to hold the tank on. :)
 
yep.....the breather hole in the bottom of the filter box is very small isnt it?...if it gets a bit of crap in it it will block.
The wee triangular side panel on the right hand side by your leg is where you access the crankcase breather hose...its where the ramair filter is meant to go.
i put mine in there, when you take the hose off the breather and pull it out, you will find its an 's' shape hose.
I cut mine thru the middle so it is now shaped in an 'L' shape. I put the short end over the crankcase breather lug and had the long piece pointing out toward me...then i put the filter in that. Now the filter sits right there so you can get at it to clean it..it makes a difficult task into an easy one.
Hope this helps.
Did you re-map after Ram air filter install? I just ran zero throttle for 24 mins. Wondered is mapping was required?
 
I left mine like Bedifferent did. No problems.

Yes Him57 you really do need to retune. What exhaust do you have ? Maybe somebody can recommend a download tune or a dyno tuner in your area.
 
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