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Discussion Starter #1
FINALLY got the carbs reassembled last night. Took forever to get parts, and the rubber plugs lost in the mail and needed re-ordered, yadda yadda... This weekend the airbox comes out and the carbs go back in.

In passing in another thread it was mentioned that I need a breather/filter for the engine which I totally didn't think about. Started looking online for basic $10 filters and started seeing some very elaborate filter setups with PVC pipes, beer bottles, some sorta bottle conversion kit, etc...

For now I think I'll just stick a filter on the end as planned since still a while before driving the bike, just planning to get it started next weekend. Ordering a few last minute parts (clamps, filter, etc)... anyone know off-hand what size I need for a filter? Not at the bike so not sure if a 3/8" tube or not.

Otherwise, just wanted to see what people have done breather wise with their bikes. Found a few examples on Google, but would be nice to see some pics and get some feedback about what was done and why etc...
 

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I believe that it is 3/8".
Just make sure that you mount it above the engine so that any oil that does collect in it will drain back rather than plugging up the breather/filter.
 

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Discussion Starter #3
Ah, which explains why some people make the elaborate filter boxes then. I'm in the 'just get it running' phase of the build. :D

Is it safe to put all the tubes into the same filter-box? (engine/carbs)
 

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Discussion Starter #5
is that ID or OD?

Seeing a lot of 3/8" where the tube slides over the end, and the 1/2" I'm seeing look like they need a coupler between the two.

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$(KGrHqN,!q8FIPWBjobOBSHuyQW87g~~60_12.JPG
 

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FWIW, I have the original airbox but I did away with the original breather separator. I connected the engine's breather directly to the inlet on the box (near the top) and inside the box I inserted a 1/4" copper elbow into the same port and connected a piece of tubing to that so that everything that comes out of it is deposited on the bottom of the airbox, just above its drain. Finally, I put a piece of clear tubing onto that drain, ran it to the left side of the bike behind the footpeg and added one of these cheap cleanable fuel filters to the end. There is no more slime on the bottom of the airbox with this setup than with the original setup. I keep an eye on the clear tubing and if I see anything in it I disassemble the filter and blow air through the element.

If you are removing the airbox you won't be able to do what I did but my point is that just about any reasonably fine filter will work and if you get one that you can open up and clean you won't have to replace it periodically.
 

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I assume you don't have the bottle breather, so yours will be a little different to mine.

You can use the same filter though!

Make sure the hose you get is suitable for oil.



 

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Discussion Starter #11
I was thinking of wrapping electrical tape around the stem of the filter or a wide rubber band, cut and wrap around. Seems that the 3/8" filters start around $9, but the 1/2" jumps to $30. Just want to grab something cheap when I order the muffler clamps that'll get here by the end of next week. :)
 

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Discussion Starter #12
What I have right now are two tubes coming out of the engine into a T connector, and about a foot of hose coming off that that plugs into the airbox. I was planning on unclamping it from the box, jamming a filter on the end, and for now just zip-tieing it up higher than the engine as per OCR's suggestion.

Once I start doing some mods (mostly aesthetics) I'll do something a bit more permanent like CXPHREAK.

So, what's a bottle breather? Because I have seen some filter mods that were actual bottles, but thinking a bottle breather is different?
 

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The bottle breather is what's coming out of Dbjacs engine. Oz CXs generally have them but it's only really a different outlet and still needs to be plumbed to a filter or something.
 

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Discussion Starter #15
Nope... not what mine has. CX500 Standard, Canadian. Clears up a few things though because when looking online I was seeing that style and thinking, no, that doesn't look right... got home and was looking all over mine trying to make sure it wasn't missing or something when I got the bike.
 

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Breather outlets were revised twice on these bikes.

The original bikes had a port on each head. Then it was revised to the 'bottle' breather in the timing inspection ports.

Lastly, TI ignition bikes had it moved to the pulser cover on the rear of the motor.

The bottle breather was also sold for retrofitting to the earlier version. I have a kit here which comes with the bottle and O ring for the bottle, the hose, caps for the head breathers and a brief instruction sheet for fitting.
 

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I put a plastic irrigation barb into my K&N filter. 3/8 one side, 1/2" the other.

Sure, the plastic will likely degrade after a while of oil exposure, but it was about a dollar investment.

Filter was $14AUD, barb was $1. The hose probably cost the most!
 

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I've been using irrigation barbs and 1/2" hydroponics hose for breathers for years. They last a lot longer than you might expect.

I used to be in irrigation so have a bit of this stuff floating about the place. Junkyard formula says use what you have. :)
 

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Discussion Starter #19
The bottle breather was also sold for retrofitting to the earlier version. I have a kit here which comes with the bottle and O ring for the bottle, the hose, caps for the head breathers and a brief instruction sheet for fitting.
I saw a 'bottle kit' for sale, but no real info for it. Having seen actual bottles in use, I thought maybe the kit was for attaching to a beer bottle or something given the name. Why is it called 'bottle'? Bell, maybe... but doesn't look bottle shaped. Also, is it better than the first style? or not really... just fewer tubes?
 

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A breather by any other name would smell as sweet .... ;)

The original breathers flow better - there's two of them. But being high on the motor and the airbox seperator is low in the bike they seem to siphon more and put more oil in the airbox than the bottle does. The original hose for the breather bottle is also too short. A longer hose looped higher allows more time for the oil to condense and drain back to the motor.

Haven't had a lot to do with TI bikes but I really think the bottle breather is the best of the lot - especially when fitted with a longer hose. I loop mine over the carbs up to frame level before it goes down to the airbox.

This is personal opinion.
 
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