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The primary case is vented through the transmission. No need for an additional vent.
Are you sure about that on this bike? As I remember the service manual indicates that the primary should run a vacuum when the motor is running. Presumably the vacuum is created from the oil pump drawing out the oil. If the primary is vented through the transmission a vacuum would not be possible. I often thought about taking advantage of that vac and running the (air cleaner) breather into the primary to get rid of the oily mess that that set up makes. Anybody ever try that? Estimated 85,000 miles and never had the heads or rocker boxes removed so the stock oiling couldn't be that bad.. I bought the 82 FXR new, it is now owned by my brother, thinking of buying it back.
 

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Are you sure about that on this bike? As I remember the service manual indicates that the primary should run a vacuum when the motor is running. Presumably the vacuum is created from the oil pump drawing out the oil. If the primary is vented through the transmission a vacuum would not be possible. I often thought about taking advantage of that vac and running the (air cleaner) breather into the primary to get rid of the oily mess that that set up makes. Anybody ever try that? Estimated 85,000 miles and never had the heads or rocker boxes removed so the stock oiling couldn't be that bad.. I bought the 82 FXR new, it is now owned by my brother, thinking of buying it back.
My '82 was Not vented either...that I know... stock... recycles or whatever, the Primary oil.
Luckily I never had any oily mess at Breather.. but... whan I do... I simply drain breather tube to Ground.
If you really wanna make an oily Mess everytime you stop... Put one of them little Filters on breather line, so it can collect oil then drool it off when ya Stop!!!
 

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Are you sure about that on this bike? As I remember the service manual indicates that the primary should run a vacuum when the motor is running. Presumably the vacuum is created from the oil pump drawing out the oil. If the primary is vented through the transmission a vacuum would not be possible. I often thought about taking advantage of that vac and running the (air cleaner) breather into the primary to get rid of the oily mess that that set up makes. Anybody ever try that? Estimated 85,000 miles and never had the heads or rocker boxes removed so the stock oiling couldn't be that bad.. I bought the 82 FXR new, it is now owned by my brother, thinking of buying it back.

'This bike' is irrelevant. What is relevant is the transmission. Look at the the top lid on the transmission. Is it vented? It is. They all are. Now look at how the primary case on later models is vented to the transmission. I am not going to give you a fish. Hopefully you will dig a little more and by that I dont mean asking for answers online. If you cannot figure it out come back with a well thought out question. Not serving answers but will help you more than you know.
 

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Discussion Starter · #9 ·
The primary case is vented through the transmission. No need for an additional vent.
i realize you are having a convo on this with ChipG56 below based on his reply. fwiw, i sat an looked at my primary and transmission and thought about your orig advice "the primary case is vented through the transmission". im reasoning that the primary case vents into the trans via clutch push rod hole. the trans itself then vents to atmosphere thru the hose barb on the top rear of transmission (which i ran a open end loop of black hose off to keep water out). lmk if im the right track. thank you
 

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i realize you are having a convo on this with ChipG56 below based on his reply. fwiw, i sat an looked at my primary and transmission and thought about your orig advice "the primary case is vented through the transmission". im reasoning that the primary case vents into the trans via clutch push rod hole. the trans itself then vents to atmosphere thru the hose barb on the top rear of transmission (which i ran a open end loop of black hose off to keep water out). lmk if im the right track. thank you

You are correct. Five speed transmissions vent the primary case via the main shaft and then out the hose barb on the transmission top cover. The key to making this work is to remove (if there is one) the seal in the clutch hub nut.
 
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