Crankcase breather.

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ithebruce
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Crankcase breather.

Postby ithebruce » Tue Feb 23, 2021 2:28 pm

Looking at a youtube clip of someone removing a breather off an R75,and i noticed that the vent pipe ran from the breather direct into the carb, whereas on my 77R100S i have the long vent pipe that runs from the front of the engine and not the breather housing at the rear , does anyone know when and why this was changed? Thanks Ian

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Rob Frankhamr
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Re: Crankcase breather.

Postby Rob Frankhamr » Tue Feb 23, 2021 2:33 pm

Different years. Up to MY '77 (I think) the old breather system was used, thereafter the expelled air was taken in a gallery from the breather valve to the front of the engine as you describe. The gallery has a small diameter hole back into the crankcase and the assumption is that it forms a settlement space where oil in suspension can settle out of the expelled air and drip back through the hole into the crankcase. If that's truly the reason, I can't see that it was very succesfull :smile:

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ithebruce
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Posts: 194
Joined: Tue Jul 04, 2017 9:45 pm
Country of Residence: England

Re: Crankcase breather.

Postby ithebruce » Tue Feb 23, 2021 3:04 pm

Thanks for the info Rob does seem a bit convoluted but hey.....BMW...Bloody hell! Lol!


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