Not price just the theory behind it. on paper it makes sense to me but looking for some input from real mechanics unlike myself. I just do **** in my garage.

 

my thoughts are, it's a relatively new thing being made and sold, and millions of Harleys got along just fine without them, and I bet far less that 1% of bikes have them since they have recently apparently became 'a thing' ..I personally don't buy into these and many other things I don't believe are necessary..some feel like they must do something and buy everything that comes along to try and help their poor fragile bikes from self destructing and it makes them feel better I guess

 

Nit clear to me the problem: it is trying to solve, The crankcase is already vented through the air cleaner.

 

For what those things cost, send me the money, and I will send you something that will do much more for your bike . . . a decal!

 

I don’t understand them, wouldn’t it cause your engine to lose pressure somewhere. After 30 years of riding I’ve never thought that my oil tank needed to breath.

 

guess its on the m8s from not enough breathing on the larger 114 to 131 engines that push way more air around. plus the old bikes had crankcase breathers and i hear the EPA cracked down on harley to plug up the crankcase more, this is what ive read hence the sumping issues.

 

I saw the video from A1 and figured I'd try it(100$x2). Got 2 , one for my 07. I know you asked for a mechanics opinion. I feel like it helps. I know even with nice big vents all drilled out over size my 07 gets pressure on the stock oil cap when I pop it off you hear that hissss. this spring Im thinking of moving the hose around to the back ,probably installing a 90 degree joint... I think it makes the jugs hotter by blocking air flow a little.
I know this can be like an oil thread, but sense im not doing much to the 2020 except riding it ., I felt like finding some sort of way to get rid of all that cash I got laying around

 

It fixes an imaginary problem.

 

Harley vented the oil tank decades ago. Most all performance shops vent the tank on certain size and up motors. So if you don’t have a higher output bike probably don’t need it. Although the M8 is problematic with crankcase pressure in general.

 

HD oil tanks are vented to the crankcase, not an open vent.