oil breather problems
Elite HDF Member
Joined: Dec 2007
Posts: 4,271
Likes: 29
From: Green Country,Oklahoma
I had this problem with a 03 that I had,everything done right,breather,vent kit,oil level half way and it still did it.Read about a guy that put a Buell oil pump on and never had any more problems,seems that at hiway speeds the oil pump does not recover fast enough on some bikes,don't know why.
Road Master
Joined: Nov 2007
Posts: 1,223
Likes: 3
From: Peoria, AZ
When you say "re-jetted" does that mean "dyno tuned"? Oil on the side can be result of an improperly tuned carb, oil level too full, or restricted breather hoses or dirty air filter [did I leave anything out?]. Also, I ride mine in the 3000 rpm range as anything below 2500 is lugging which will imbalance the process, also. Misting is "normal" since it DOES vent into the AC and tends to build up in the filter and oil tank over time so it looks worse that actually is esp on long rides. If you go with the separate vent filter, keep it clean or it will leave puddles and mess when you ride anyways [esp on tires and brakes where you DON'T want oil]. If it's barfing oil, that's a more serious problems.
Stellar HDF Member
Joined: Dec 2006
Posts: 2,906
Likes: 11
From: Grottoes Va.
There was a service bulliten a few years back about a fix for this, it came from Buell, involved countersinking the seats for the umbrella valves deeper and drilling out the drain hole in the heads. I can't remember when it was exactly, go to sportster.org and do a search for buell service bulliten or oil blowby, that should pull it up.
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Cruiser
Joined: Jun 2009
Posts: 172
Likes: 2
Blowby
While blowby is a common problem on Sportsters, it isn't normal. We have two Sportsters, both 883s. One has about 12,000 miles on it and the other has about 32,000 miles on it. Neither one of them puke oil into the ham-can air cleaners. I can run mine around town or I can take it out on the open highway and run it at 90+ for long stretches. Not a drop of oil inside my air cleaner. We never need to add oil between oil changes either.
So the answer is, No, in fact they don't all do it.
So the answer is, No, in fact they don't all do it.