oil in air breather
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,416
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From: Honah Lee
Check the oil
Be sure when your motor is hot/hot that the oil level is at the correct level. Read your manual on how to check it since newer sportys are different. If you have a modified air filter with the open back it's going to do this. They all do it. Mine is not so bad as long as I keep it under 3000rpm. Then I only need to wipe its chin weekly
Last edited by Jackie Paper; Oct 17, 2010 at 12:11 PM.
Road Warrior
Joined: Sep 2006
Posts: 1,278
Likes: 2
From: Mission,BC.Canada
This is a normal condition for Sportsters. It's called blow-by. The simple cure is, keep the oil level at the lower end of the dip stick. When you check the oil level, the engine should be hot and the bike on the side stand.
Tourer
Joined: Oct 2010
Posts: 285
Likes: 2
From: san jose, ca
Cruiser
Joined: Mar 2010
Posts: 142
Likes: 0
From: Beaverton, OR
Along with everything else posted check your owner's manual for the proper technique on checking the oil level. My Ultra needs to idle 1-2 minutes before I shut it off to get all the oil back in the sump. If the level is checked and filled without doing that filling the bike to the fill mark will cause it to have too much oil. I do not know if this is true for Sportsters.
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Supporter
Joined: Jan 2007
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From: along the shore of Mishigami
May want to check the oil vapor hoses coming your cylinder heads for any cracks. They are rubber and won't last forever. When I had my Sportster I kept oil quantity about 3/4 full just for this reason.
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Road Master
Joined: Sep 2010
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The only real way to "solve" this problem is to smack Harley engineers upside the head and make them design a decent breather system. To "band aid" fix the problem there are a number of crankcase breathers out there that route the oil to a catch can or straight down to puke on the ground as you ride. It's a very common problem w/ Sportsters and it's due to a flawed design on Harley's part.
Seasoned HDF Member
Joined: Jun 2010
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From: Upstate New York
It's been a steady problem with big twins as well.
Running the oil level low MAY help, but I've found that it increases operating temperature of the engine, and increases oil consumption. Not a good solution, IMO.
Running the oil level low MAY help, but I've found that it increases operating temperature of the engine, and increases oil consumption. Not a good solution, IMO.