Ok all you Husky Guru's- why is this?

I'm partially restoring a 86' 510 TX and noticed this while primering the frame.
I turn frame on it side and oil starts to ooze out of frame at the foot peg weld. Appears to be used motor oil.

Why and how could there be oil in the frame? Not just a little but about 4 oz and keeps on coming.

Any ideas?

My 78-OR390's frame split when it was a year old from water being in it and froze. Husky frames are tough, but the welds have always been done----rapidly? To be kind.

I'm FAR from expert or in fact know anything at all about old huskys. But I think a few motos vented the oil breather to the frame. Is there a hose fitting up near the headstock?

Nope, that's not it. The breather tube vent's into it's own plastic canister that is mounted below tank.

My only conclusion is a blown counter sprocket seal that was spewing oil on the frame and found it way thru the hole in the weld. The positioning of the sprocket and footpeg weld would indicate such.

Check the plastic canister - Does it have an inlet and outlet?
The outlet side should have a rubber tube attached, this tube is then pushed into hole in frame down tube ... many times this outlet tube is missing ...

Yes, the canister does have one inlet on one outlet.
The hose is long gone. I suppose this oil is old and from a time that the hose was connected.
Well. at the very least the inner frame tube is well lubed!

I believe that you have a very rare prototype Buell/Husqvarna dry sump engine frame.
only two were ever made and the frame held all the motor oil that fed the dry sump engine.

the other complete bike was just purchased by the Motorad museum in Stutgard for 15k US dollars!

At least thats the why i remember it.

J.K.