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breather question

Turk55

Active Member
So I changed to a open air filter that has the rubber hoses from heads to air filter housing, problem I am having is even though I run 1/2 quart oil it doesn't take long for oil from heads to clog up filter and air censer in the throttle body causing problems enough I have to remove filter and clean everything. My question is can I remove the hoses and replace them with some king of breather that isn't connected to air filter.
 
I understand what you are asking with your question, but clarification might help in addressing what you are experiencing.

Blow-by comes from the engine and can't be reduced by an air cleaner. Some air cleaners/breather systems are better than others at keeping the blow-by off the engine/pants legs.

All internal combustion engines have some blow-by, there are a few reasons for excessive blow-by on a newer bike-

Oil level- HD says to warm up the bike, shut it off, let is set for a couple of minutes and if the oil level is below the bottom line to only add enough oil to bring it to the midway point between the two lines.

Oil Viscosity- If the ambient temps are above 50 degrees, HD says to run 50 weight oil (not 20-50), and if the ambient temps are above 80 degrees to run 60 weight oil.


Umbrella valves in the rockers not functioning properly- Of course they should on a newer bike, but they could have been defective at install, and they do wear out.

Crank out of round- an out of round crankshaft will cause More than the normal amount of blow-by.

Since it sounds like you have more than the normal amount of blow-by, I would first check the above 4 items.


Then it is a question of what to do with the normal amount of blow-by.

Most new air cleaners are EPA compliant and dump the blow-by into the intake, and most will handle normal levels of blow-by without dripping, however, they do compromise the performance and longevity of the engine.

Engines like (run better/make more power) cool dry air, not hot oily air.

The oil being dumped into the engine will build up carbon deposits in the combustion chamber which brings on a whole new batch of problems, especially with EFI bikes.


A few companies still make air cleaners that have breathers that route the hot oily air into the atmosphere. The Outlaw HiFlow 587 does that. With systems like this there are a few choices on what to do with the blow-by.

1. Breather Bolts These work well on bikes that do not have excessive blow-by
2. Traditional Hose/filter breathers These work well with bikes, even if they have excessive blow-by, but the filter does need to be cleaned periodically
3. A variation of the Traditional Hose/filter...it does not use the filter, but runs the hose down to the ground, keeping the oil off the bike and the rider. Another variation is running the hose into a "catch-can" that gets emptied periodically.

If you are wanting to stay legal and route the hot oily air into the engine per EPA mandates, one of the best for doing that is the Pro Billet Air Cleaner.
__________________
Kevin
 
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Have you had or changed out the Rocker Box gaskets lately?
If the bottom gasket is on wrong it will mess up the breathing of the Umbrella Valve.
tourbox
 
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