Oil tank Venting

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olympus

olympus

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Hi Guys
When either BMC or K&N conical air filters are used where do folk vent the oil tank into? ... atmosphere, into a bottle??
 
If you have a ham can air filter originally (not the black plastic thing of 850 MkIIa and MkIII) return to the original and use a full size K&N air filter. Air cleaner modifications eliminate good features such as a place to attach the ignition switch. Chrome the front ham can plate and it looks like a custom air cleaner for a 60's muscle car. Stainless surround is a nice touch also.
 
On my Featherbed I run my breather from the motor as well the oil tank breather into a 1 ltr with a screw top catch bottle that sits in between the rear engine mounts the two hoses fit tightly in the screw top but the hoses go to the bottom of the catch bottle and a few breath holes at the top of the catch bottle to let out excaping air, been like that for 37 years now.

Ashley
 
I must be doing something wrong. (My wife can attest to that)
I have a Mikuni with a K&N filter. I left my oil tank breather attached
to it's spigot on the ham can filter backing plate. I get no oil, splooge,
or even enough vapor out of it to attract any dirt. Yes, I have verified
that the hose isn't blocked. I never fill the oil tank higher than half
way below the high mark on the dip stick. Oh!, I have a Comstock
sump reed breather.
 
On my 73 850 I vent to a small bottle that's wedged between the battery and the rear air cleaner box plate thingy. With the Mike's XS crankcase reed valve and 6500 miles on my rebuild I get very little to zero ooze in the catch bottle. Long fast 75-85mph freeway drones puts a misty coating inside the bottle. Nothing in normal operation.
 
In 37 years of having my catch bottle I have only got a dribble of oil in the bottom of the bottle, its more air from the tank and motor that excapes into the bottle not oil and with the reed valve on my motor no air gets sucked back into the motor.

Ashley
 
Oil tank Venting
Oil tank Venting


I installed Mikes reed valve and vented the oil tank....a very small amount of fluid makes it to the reed valve but never further.
I ran a catch bottle on a couple of high performance automobile engines with very little if any fluid trapped as long as the PCV was in place.
 
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IMO, a catch bottle catches little or no oil unless it is filled with a scrubber media, and the in/out plumbing is arranged to force the crankcase vapour to pass thru the scrubber media.

Oil is carried by the crankcase vapour as a mist or "fog", and passes thru, and exits the bottle without being deposited in the bottle unless a scrubber media is present.

Slick
 
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olympus said:
Where did you get the breather filter from please??
Click to expand...

Summit Racing. They offer a wide variety of size and filtration applications. Their shipping costs suck, check Fleabay too.

lazyeye6 said:
What does the breather filter, filter?
Click to expand...

Any vapor, fluid or particulate passing through the crankcase and making it through the the oil tank or beyond. I installed it primarily as CYA protection.
Call it a vapor filter...and I wanted a secondary level of protection from oil getting spewed all over the rear half of my bike. Just another level of control.
Texas S offers a realistic insight.
 
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