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1980 XR200 breather hoses

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I would like to replace the breather hoses on my 1980 XR200 with new ones as they are rock hard now. 


I'm not sure whether the best choice is just to replicate the hoses and fittings exactly as they are now with new hose, or to upgrade. 


I remember reading in a thread a while back that there was a better way to do it, but I just can't find it now by searching.


There's also some who redo their bikes breather to have a car PCV valve and filter at the end, but not sure if that's a good idea for the XR200.


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The XR with its shared sump has different venting requirements than a separate engine crankcase and tranny. A good example is my CRF250X with an engine vent from the cam cover (which has a vapor separator) to the engine side of the airbox, and an open ended  vent from the tranny.   The piston up/down motion displaces air on the crankcase side just as it does on the combustion side so lots of air pulses in the crankcase. In addition there is some combustion gas added to the crankcase from ring leakage.  On the  XR the volume in the tranny helps absorb those pulses before they enter the vapor separator in the roof of the tranny.  The result is air pulses in the vent hose with a net outflow from ring leakage. Honda didn't think this was a problem because the OEM hose had a T near the tranny with one hose going up and one going down with a duck bill valve on the end to keep road dust and water from entering.  All of the duck bills I have examined were hard from age and dysfunctional, and it is a short hose distance from the duck bill to the tranny. Since I often encounter water that is deeper than a foot I always worried about water ingestion into the tranny. My riding also involves dusty conditions and I don't want dust ingestion. 

So I altered the vent system by removing the duck bill and plugging the vent with silicon. There is a possibility of condensation collecting in the down tube and annual cleaning is needed. I then added a gauze filter to the end of the up vent; several types are avail in plastic and metal. Here you can see its location and how much dust it filters.


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