we use a simple PCV and stop the back returning negative air doubling the amount in the engine

well that's my shop

 

And I wouldn't dream of putting anything in the vent line.... Learned from Drag Racing, to use an open catch can... wide open but still catch!!
Much as I hate to put anything [I'm even uncomfortable with the filter] in the return oil line..
These poor old Buggers cannot breath, nor evacuate oil, as it is...

 

I realize I posted new technology for an old concept in the shovel forum...yikes LOL.

But that open vent hose to the atmosphere just bugged me and had to do something about it. Just wanted to prevent any potential mishap in the event oil gets under the tire especially at higher speeds....not to mention it also protect the environment. This catch can filtering system allows air pressure to pass but contains the liquid.

Racepres - isn't a catch can a requirement for drag racing?

 

Tisk Tisk! Don't introduce any new technology that works! A beer can is acceptable however but it must be Pabst.

 

Yes indeed... a Must... but it does Not need to be in the least bit restrictive...Our Dragbike catch can had a Hole about 2-1/2 inch diameter for the can to Breathe, out the top... No Filter there either... just a hood...... Actually in all things Harley [Old pre Twinky type Harleys anyway] any restriction... anywhere is a Bad thing for the old Girl... Do What makes ya feel good I guess...

 

2 1/2" dia hole at the top...that is a huge hole. Thanks for the insight...I will probably remove the 3 filter layers at the top for better air flow. Those filters were designed to eliminate blow-by and oil escaping out of the top of the catch can. Don't think the vent hose releases that much oil or I just haven't seen any visual residue.

 

If ya run the engine as hard as they get at the Racetrack...you will find oil...the poor engine cannot get rid of the stuff...so
to really let 'er rip, and seeking a Win or Record... we Bypassed up to 90% of the feed oil back to the tank... Friend of mine... who could Beat me, more than I could him,... would bypass all oil!!! During a run... than turn it back on in shutdown!!!
Some of the Hot guys today, use an evacuation pump to try to draw on the Crankcase... this was illegal back in the day... but now, is considered a safety measure on extreme Harley Engines...But... I digress... these are decidedly Not Street engines..But, the need to Breath, and get rid of oil is Universal...Still Harleys after all...

 

I am a cruiser and not a racer...I've only cruised at around 70 mph on 1/2 - 3/4 throttle and have not gone WOT yet.

However, it felt like I could go a lot faster. Surely would like to find out what this bike is capable of doing.....but I value my life LOL.

 

you live more flat out in a few minuets then most an entire life

 

In my research on catch cans, I did ask about air flow.....interesting reading about how much air passes through the breather system i.e. Breather System Air Volume Text....more applicable to newer bikes but probably still applicable to older Harley's.
.http://www.dkcustomproducts.com/brea...ults-video.htm