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_JoNeS_

FAO Grayracer - Oil breather mod

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About to finally get round to re routing my oil breather (bikes been in bits for repairs), basically I want some advice on whether this is the best way of T'ing the hoses, ive taken photos placing the hose and T where a plan on routing them. I have bought a 1m length of silicone hose 12mm ID, various hose clips and a K&N style filter, I don't plan on using the stock hose as I would like to save it if I need to return it to standard. Anyway here are the photos. Thanks in advance.

DSC00669.jpg

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You can see the hose running down by the side of the shock, seemed the best place to route it ? dosen't seem to foul anything.

DSC00671.jpg

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The other peice of hose of the T I plan to route through the rubber mud flap under the seat attached to the airbox, It will have the filter attached as follows.

DSC00676.jpg

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very nice job man!

what do you need the swingarm hose for?

i put a protective tape on the valve cover cuz the hose was rubbing against it preety bad.

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Well done, Jones. The layout makes perfect sense. The only thing that would improve it is the addition of a rubber "reed" type check valve on the bottom end, but that isn't really even needed.

what do you need the swingarm hose for?

If you look how the plumbing is laid out, any oil exhausted from the cam box would tend to flow straight out and down through the down hose, instead of gathering in the air box. Nearly perfect.

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it can suck sand and water.
Not with the line running to the air box, it can't.

In the first place, if you apply a vacuum to the hose at the engine that is high enough to cause air to flow through that hose at 100 cfm, that airflow will only be half that on either of the two end lines, the ones running to the air box and downward.

In the second, if, with that vacuum applied, you stick the end of the lower hose in water, or whatever, the resistance posed by trying to lift anything up through that hose will cause 100% of the air to flow in through the air box hose instead. It's a simple, effective vacuum break.

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Looks good! I plan on picking up the material and doing that tonight. I like the idea of going just under the airbox to keep the oil from spitting into the ab.

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Looks good! I plan on picking up the material and doing that tonight. I like the idea of going just under the airbox to keep the oil from spitting into the ab.
If you do it the way Jones has done, you'll get little or no oil in the AB. The only caution I would give is to use a T that has as near a full 12mm ID as possible.
What is the advantage to re-locating the oil breather? Just wonderind.
To reduce the possibility that the engine will suck in a load of water or sand on the piston upstroke while starting, or as it stalls.

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Cheers for the thumbs up Gray, finished it up tonight, looks alot cleaner without the hose running down the side of the frame, (but thats ovuisbly not the point of this mod).

DSC00668.jpg

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If you look closely you can see the T in place with all the jubilee clips attaching everything together. I made sure I zip tied everything secure to prevent any interferance with any other cables etc.

DSC00663.jpg

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Here is the small K&N style filter secured in the airbox, I used a heated up screw driver to start the hole in the rubber mudflap, I then cut small slits around the hole with a stanley knife until it fit through (tightly though to prevent dust entering).

DSC00660.jpg

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It just pokes out near carb overflows, Don't think I should have to cut it down ??? I thought it might be dangling a bit low ???

DSC00665.jpg

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