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Hi All,
Another question from the newbie!
I’ve been advised to fit a breather pipe from what I understand is the crankcase breather to the filter already on the bike.
There is a brass connector in the crankcase but I believe it’s the wrong fitting? I have sourced the right fitting (I think) and some pipe.
Having trawled the internet there seems to be mixed opinions. Some say connect to the filter and others say just leave the pipe loose under the bike.
Any opinions/advice?
Thanks
If you want oil dripping out of your air cleaner, connect it to there. If you want the inevitable oil mist to be dumped overboard as you ride along, leave it as it is. Up to you.
The breather to air filter was an EPA mandated move. Before that, everyone did their bit to keep the dust down on the road by spraying it with oil.
I’d suggest you go with Johnjzjz’s suggestion. You can’t go wrong with what John suggests.
For my own reference I am real curious on the opinion how that pvc valve impacts a bike that is puking from the sump after a long layover? Maybe the extra hose up and over the oil tank helps contain the mess? It sucks back in???
My breather vents to the ground. After a long ride I may get a dime size spot of oil out of it. I should add the entire machine has been rebuilt. The transmission internally was the only good to go component when all was torn down and inspected.
My current setup is a totally stock routing of the oil lines. Primary oiler & return is intact. I did turn the rear chain oiler way down - hardly need a drop there. Others seal
the primary and shut the rear chain oiler off. I did that on my first shovel then went dual belt drives - phase3 & Supermax kits.
Winter layover has it sitting with an empty oil tank and a new oil filter. Just add oil in the spring. I leave piece of tape over the ignition as an extra reminder she’s dry.
iam pretty lucky as my 82 flh doesn't wet sump, not forgetting the bike only has 11000 miles on the clock. I did a 55 mile ride last Saturday , parked it in the garage , no leaks. Before i fitted the pcv, i would always get a tiny little puddle of oil from the breather hose , I also have the stock setup with a wet primary. OK so I also own a 1964 G15csr Matchless which has the Norton 750 Atlas motor which is notorious for crankcase breathing problems and the factory did some half arsed tweaks during the early commando production in the 70s. Blokes who rode behind me on the Matchy would complain about a fine mist of oil on their goggles, as i had the crankcase breather hose fitted to the rear of the rear fender. So i put a pcv on that bike as well same story when i would park the bike after a ride , guaranteed a small puddle of oil under the rear fender, now with the pcv no oil puddle......gotta be happy with that
I’d suggest you go with Johnjzjz’s suggestion. You can’t go wrong with what John suggests.
For my own reference I am real curious on the opinion how that pvc valve impacts a bike that is puking from the sump after a long layover? Maybe the extra hose up and over the oil tank helps contain the mess? It sucks back in???
My breather vents to the ground. After a long ride I may get a dime size spot of oil out of it. I should add the entire machine has been rebuilt. The transmission internally was the only good to go component when all was torn down and inspected.
My current setup is a totally stock routing of the oil lines. Primary oiler & return is intact. I did turn the rear chain oiler way down - hardly need a drop there. Others seal
the primary and shut the rear chain oiler off. I did that on my first shovel then went dual belt drives - phase3 & Supermax kits.
Winter layover has it sitting with an empty oil tank and a new oil filter. Just add oil in the spring. I leave piece of tape over the ignition as an extra reminder she’s dry.
it was also interesting to me in the beginning when we tried that on the shop bikes - 2 years later i knew it worked and continued to do the job we were looking For
2 things happen - 1 the hose makes the sump oil clime over a foot vertically and yes we sometimes see a few drops but the drain pan is not needed
2 - if you understand how the oiling system in the venting and breather actually works its a add and not a subtract to put the one way valve in place
first thing it does is stops the extra air from coming into the exit vent — an a abundance air the engine system does not need or want < this is the thing we looked at closely - by stopping the in coming air from the 2 pistons together going upward every other time the crank goes around - using a one way valve - you do not over whelm the breather system and you do not make it ineffective - reason it only has around 1/2 the air to expel as it did before the valve was in place note the piston returning to a downward motion causes a blow back into the cam cover to lube all of the pieces in the cam cover - then add the air that is sucked back in it becomes over pressurized in the cam cover as the exit is a pipe but its baffled so it can separate the liquid from the air — then at slow engine speed it ok at hi way speed it becomes inop in its ability to work correctly add miles to the engine and piston ring compression loss even adds more air the an already over pressured system - the guys who run this have been happy the way it works cuts down on floor oil and gasket blowouts or the cam seal dreaded cant stoop the leak even with the new seal
been using this better then 10 years it works for us this is that really matters to me
Thank for all the detail. Okay, I shoulda done this from the start. I’ll add the pvc to the end of my breather as it sits. Looks like harder to find the pictured than I thought, out of stock so far. I know can prob go to Napa or other auto store and find a suitable pvc valve. That would do? Positive - aka one way valve. I hardly get a single drop, when I do and it’s not after every ride. I mean tiny like a dime or tip of your pinky. The only time I sumped was on startup after 6 months, 8oz + or - maybe. What sold me to try the pvc is the statement about the cam cover. Had mist only one time along the leading edge - front - I gotta pic somewhere.
I was WTF now? Never came back….
Also I have placed my finger over the breather and felt the blow and suck pulses - I understood. July 7. I cleaned this up never came back. Crank pressure?pushing past cam cover, makes sense.
Last edited by Ytcoinshooter; Oct 20, 2023 at 05:52 PM.
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Breather pipe
