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save the aggravation run the tube down the frame and vent to atmosphere. Problem solved .Did it with all my bikes works great .I run it down to just aft of trans hangs about 1" below frame
Yup, did that on my previous 106 Dyna build. No problems
Plus the crankcase area for a Harley motor is a lot smaller than a car engine. Using a 3/8" hose is probably adequate for the engine size.
I know whenever I go look at a used car I pull the pcv valve out while the motor is running. If air is blowing out the hole I know the motor is worn out and has a lot of blow by and I pass. I don't care how low miles they say the engine is.
FWIW, I measured the holes in my factory breather bolts to be 3/32” diameter (that’s the hole on the threaded end of the bolts, they were smaller on the end than the hole that was on the side of the bolt). That was the most “restrictive” point on the stock setup, that I found. If you use something with 3/16” diameter ID that’s almost 4 times the capacity of 3/32” diameter... so if the ID of your fittings are close to 3/16” it’s gonna breathe fine... and bigger ain’t gonna hurt either lol
Formula is Pie Times Radius Squared
Theres a couple of threads on this with plenty of pics, heres mine or you can just run down and under the frame like stated above.
Originally Posted by OLD 96
A stealth catch ,pill bottle, can. I love it.
I did this also but got tired of removing cover to empty pill bottle, so I drilled hole in bottom of pill bottle and siliconed a larger hose and ran to bottom of bike. About three inches below frame. I used black fuel hose from oreilly and it works great and it doesnt make a mess on the frame or below the bike.
Drill you a couple of holes in top of pill bottle which vents gas inside of breather. You definitely want things to vent.
I did this also but got tired of removing cover to empty pill bottle, so I drilled hole in bottom of pill bottle and siliconed a larger hose and ran to bottom of bike. About three inches below frame. I used black fuel hose from oreilly and it works great and it doesnt make a mess on the frame or below the bike.
Drill you a couple of holes in top of pill bottle which vents gas inside of breather. You definitely want things to vent.
I was actually going to drill a hole and run a hose down and under the frame, thats what I did on my old Evo, but I was a little lazy and wanted to try this instead, Ive since changed it, I removed the T splitter and have two hoses running into the pill bottle.
Lots of people will just lay a Kotex in the bottom of the air box and just change it once in awhile. Depends on your " Flow rate " you may need to change it monthly.
Not a fan of a catch can style setup, I'm a vent to atmosphere kind of guy. Especially those metal ones hanging and possibly banging around. With that being said, I do get a little worried about the slim possibility of oil getting on my rear tire. I ran tubing straight down from the backing plate, under the tranny side cover, and zip-tied a very small K&N breather filter on the end. This way, I have constant venting and no restrictions, and almost no possibility of pure oil making it to the tire.
Last edited by twincam10353; Jan 4, 2021 at 11:01 AM.
Educate me.......other than NOT recirculating stuff back into the combustion chambers of the engine what are the positives? More HP?, better performance? what?
Personally IF it's just to make the engine "last longer" then I'm fine with it being kept stock since I know my engine will probably outlive me because I only put about 4 to 5,000 miles a year on mine.
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.
Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.
Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.
