Author Topic: Oil breather, do i need it? (Read 4727 times)

stian · « **on:** March 19, 2006, 05:43:18 PM »

I've seen several places that people are putting a small filters on a wire going from some place on the engine.. And came to the decision that this is what a oil breather is.. am i right?
What im wondering is, is this necessary? What does it do? and Where can i buy it, or maby fab something my self?

jeepskate99 · « **Reply #1 on:** March 19, 2006, 06:09:19 PM »

You only need it if you run pod filters.

2005B12S · « **Reply #2 on:** March 19, 2006, 07:43:21 PM »

That is the crankcase vent. It is vented off the top center of the valve/cam cover and connects to the airbox. As stated above, if you run pod filters -no airbox- you need to provide another method of venting such as a small aftermarket filter.

You should only get crankcase gases out of this vent unless you are running a very high compression race motor or have bad piston rings. In either of these cases you could see a small (hopefully) amout of oil.

Ride On, Ed.
2005 GSF1200SZ
1983 GS750ED
1992 900SS

Red01 · « **Reply #3 on:** March 20, 2006, 05:38:13 PM »

Quote from: "2005B12S"

You should only get crankcase gases out of this vent unless you are running a very high compression race motor or have bad piston rings. In either of these cases you could see a small (hopefully) amout of oil.

Not true. All engines will vent gases out. That's why the hose is connected to the airbox on a stock bike, to burn the gasses. The others mentioned will vent more though.

2005B12S · « **Reply #4 on:** March 20, 2006, 08:59:21 PM »

That is what I said, you should only get gases. I have seen small amouts of oil vented on high (11.25-1 on a GS 16v head) compression motors when run very hard.

leasingguy · « **Reply #5 on:** March 21, 2006, 12:07:38 AM »

FastByGast sells an electric pump that the pro stockers run to pick up a few ponnies. It's used to create a vacuum in the crankcase to help the rings seal. ;)