Yes, really.

If you haven't heard of it before shows that you haven't been around much.

Of course they come from the factory with the crankcase vents into the engine air intake to meet EPA requirements, but that does not mean that it's best for the engine.
It causes carbon fouling in the combustion chamber, and often wets the air cleaner element with oil.

 

If you read 4 quarts you must be looking at the capacity for some other model...

The capacity for a Softail tank is about 2-1/2 quarts, Evo or TC.

 

I'm sorry i haven't "been around." I was just asking a question, no need to get defensive or whatever that was.

I new they vented back in, just didn't know for sure why if it was bad for the engine. Although if you look at a lot if not most automobiles do this, and there are a lot of vehicles with a high amount of miles on them, it makes me wonder how bad could it be unless you were to overfill your oil.

Just my two cents, i don't know a lot, that's why i'm on the forum.

 

best to ignore members full of them selfs and respond only to members who want to help, rather then put you down. Those we call trolls. Don't feed them and they'll go away.
Not callin you a troll Ron. Just tryin to make a point.

 

Good call, been on the forum for a while just don't comment too much. Thanks for the advice

 

Look back at the manner in which the query was presented - it was suggestive that the other member didn't know what he was talking about.

Just to add, yes cars have used the Positive Crankcase Ventilation (PCV) for some time, and it does cause fouling, and this has become even more problematic with the latest Gas Direct Injection (GDI) with Turbo engines.
Many folks add catch cans to the PCV system to minimise the fouling.

Another EPA device that causes fouling of throttle bodies is the Exhaust Gas Recirculation (EGR), which your engine could do without.

 

I don't know anything about an EGR Ron. Would be nice if cyou would elaborate here since it relates well with all that is anti EPA. And I hope you didn't take my comment oersonal please. The OP felt like you may have come on harsh. Since he/she is knew here, I thought that commenting that trolling does not need to be tolerated. But always its best to ignore.
Lets just drop that part since there has not yet been any finger pointing, Cool? Thanks!

 

Here's a fairly good write-up on the EGR - a few manufacturers used it to reduce the NOx emissions.

http://www.cambustion.com/products/egr

Not heard of it on motorcycles.

 

got it! Looks to be more of an issue related to diesel fuel. But not limited to regular gas. I'm guessing that O2 sensors work in a similar fashion. Hence the reason why an EGR is not required on bikes. Not yet anyway LOL

 

The gas engines use EGR extensively, with O2 sensors.

It all depends on the manufacturer what technology they use to achieve EPA compliance.