Question about oil pipe

[virginiapier]

Hello,
I want to replace the chaincase on my '44 G3L and I've noticed what looks like a 4-inch oil pipe coming out of a union on the drive side main bearing. What is it connected to?

[Groily]

If you're talking about a pipe off the union as in the pic (albeit of a later engine), it's the crankcase breather. Let's pressure out, so just goes to atmosphere.

G3 crankcase drive side.JPG

[clive]

If you're talking about a pipe off the union as in the pic (albeit of a later engine), it's the crankcase breather. Let's pressure out, so just goes to atmosphere.
G3 crankcase drive side.JPG

And often drips a bit after you stop the bike, or just as often spreads a bit of oil vapour on the underside and the back of the chaincase. More drips!

[limeyrob]

This is the one and only time you'll be able to get to it so put a new bit of tube on!