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Discussion Starter #1
So after driving one of my bikes for a while i noticed a fine mist of oil gathering dust on my pretty black engine so here is what i did to fix



the breather hose issue once and for all i am going to contact the filter manufacturer and see if they can do this in production



the elbow i used is by dayco for some car emission thing it is part number 28623 comes in ones or a pack of 5



pardon my lousy pictures but you will get the idea



















make the hole smaller than the fitting so it seals and holds the elbow



MAKE SURE YOU BLOW ALL THE RUBBER DUST OUT OF THE FILTER BEFORE INSTALLING IT!



no more mist or loose hose yeah



and yes this is not a twin but the idea is the same i will post a pic of one of my 650s later lol
 

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Question.

Since this is a pressurized vent (meaning that the vent pushes a fair amount of air), would it make sense to run a splitter to both pods to keep the carbs equally balanced?
 

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My last one I just routed it under the bike in a small catch filter. Oil vapors have no place in fuel or the combustion process imo. Unless its a triple
 
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Saw one of our bikes that had the breather hose elongated and run all the way back under the seat. Not certain I'd want the mist around my back tire, but then again, at speed it would probably land less there then the usual exit.
 

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I'm with cxlover on this one.



Here is my answer. Not for everyone but it was cheap and easy. I started with a T section that I blocked off one side (obviously an L would be better, but I used what I had on-hand).





Rerouted the hose to vent into a Uni filter, sitting inside of a brake cleaner lid which now acts as a catch cup for any oil mist that gets past the filter. In one of the universes strange coincidences, the lid is an EXACT fit between the frame and the rear inner fender.





No oil on the ground, tire, or engine, and a handy dandy catch pan.
 

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I didn't realize this was a problem. I just ran a longer hose. I have a hose from the breather on my 650 (same exit as GL500), which I take up between the carbs and then rest between the V, just aft of the rubber shield that the temp sensor wire passes through to get to the thermostat. I attached a filter to that (from the "Ricer" section of Auto Zone), and I've never had an ounce of oil mist there. Getting that kind of height above the breather means no oil can make it up, but air has no problem



Now, if you have a CDI CX with the breathers on the heads, you that's a different issue.



What I'd do there is keep the stock T, and run the big line zip-tied to the frame rail, leading backwards. Once you get to the main downtube, attach another "T" adapter. Attach the T adapter so that one of the top arms of the "T" is attached to the breather hose from the engine. The other side of the "T" should be attached to a length of hose, which has a filter on the end. The bottom part of the T, attach a hose that goes straight down, and then plug the end.



Oil will accumulate in the hose that goes straight down. You'll have to empty it infrequently -- just like you have to with the stock airbox.



The better alternative, however, is to block off the head breathers (just attach the hose from one breather to the other), and use a breather off of a Euro-spec CX500. You know, the little thingy that attaches to the inspection port.



I've done this when converting GL motors to CDI, and didn't want to swap perfectly good heads. I just slapped on a euro spec breather and it worked perfectly.



So now with that euro breather, you can have one hose that goes up to the V and has a filter attached, and you'll never get oil mist.



Charles.
 

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Discussion Starter #10
again the problem i saw was condensation build up and it has to be evacuated but al do what they want



check inside one of your rocker covers in cold weather it wont happen now



misting was more a issue of the way the engine in this case has the clearances set so it blows a little till its warm



they are not stock pistons or rings
 

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Here's another approach - I just bought one of these and will do some minor modification on the fittings to accept the breather hose - a small breather filter will go on the rear fitting. I'll probably drill and tap the top for a fitting to accept the breather hose from the heads or replace the front fitting with a larger L-fitting. The aluminum bottle is small enough to stand next to the battery repositioned as Tim did and clamp to the battery bracket:



http://www.ebay.com/itm/171023520049?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649







A bit more expensive than a plastic cap but more finished looking. It will catch the mist and look good doing it and be less likely to pop out of place. On my bike it will be behind a side cover, but I'll know its there....
. I thought about using a second one as an overflow coolant bottle but its a bit small.



VC3
 

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Hey Murray on a CX650 would you do just the one hose or use a T and put an elbow to both pods? I have the stock carbs for now...and really like this over using a filter. Just don't want this to cause any running problems


Sent from my iPhone using Tapatalk
 

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I was also having issue with oil spitting out all over my rear end (I'm using casing from both a CX and GL), and have since extended the breather hose from what I gather is the same method as ChopperCharles. Went for a pretty hard ride after the mod to see if there was any indication of oil leakage via the filter and so far, there is none. :D
I do plan to re-route the fuel hose without kinking if needed, as it does make contact with the intakes a bit which get super hot and unsure what temperature these hoses can handle. The hose appears kinked closer to the engine case in the pic but is deceiving as it's the braided sleeving that is exaggerating the slight bend.

breather.jpg
 

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**EDIT/SUMMARY**

My modification blows. Literally, it blows. Went for a ride to the city at highway speeds, only to find a dangerous amount of oil all along the rear again, so back to the drawing board on this one. @*&$!
 

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Have you considered using a drainable breather seperator CE?
Sorry for the late reply CXPHREAK. Yes, I've definitely considered an oil catch can, and still may go that route. Personally, I think the main issue is the amount of pressure that is being built up in the engine with the only one escape of combustion being through the single breather. I've noticed that there seems to also be oil seeping through the casings when the bike is ridden at highway speeds - (this is the second set of front and rear gaskets used direct from Honda when the engine was out twice), and I made fully sure that where the casing surfaces meet, they were as smooth as butter. Kameron and I are led to believe that the single breather that is being used via the inspection port is not enough at this point, which I fear the only other sure way option is to drill the spots that are blanked off on the current GL heads while still keeping the breather on the timing port opening. So basically 3 openings for engine to breath. Just very shocked that the oil/pressure is enough to pass on the extended tubing past the filter. I can understand if there was a small amount of misting, but this is far from that.

Any other ideas that you or anyone else may drop, please feel free to post.
 

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You can use a front brake reservoir.

Plum it to the breather outlet.

Tap a barb fitting into the lid to fit the breather.

Stuff it with steel wool as a baffle.

Watch the oil level and drain as required.


EDIT: Something like this would look good mounted somewhere.
Universal CNC Front Brake Clutch Tank Master Cylinder Fluid OIL Reservoir CUP | eBay
That would make a super clean resolve dbjac, but I think as stated to CXP, I think I have to target my 1st assumption I think is in question first as I really don't want to be blowing gaskets and s**t.
 

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Breather tube options

on my cx i just ran one from each head to each pod with new lines and got rid of the factory t



but i guess you could add another t and hose bits

So you used two breather pods or kept the same "T' and used one or does it matter? 78 CX500? Or did you junction into the air pods that came with carbs?
thx
 
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