so my 73 750 burned oil from the pipes since i got it running. The motor had been rebuilt by a local brit bike shop, i put about 500 miles on it then took it back to the shop to look at that issue (my guess was the oil was coming from the head) so things come up, the owner goes on vacation, etc, it leads to the bike sitting in wait for about a month. Today he got to work on it, calls me up and says "we started it up and it's 'spewing oil' from the motor where the barrels meet the bottom case. Now besides a leaky tach drive this thing never leaked any oil. Opinions on what might have caused this? Could this possibly have been caused by sumping and maybe the pressure from the amount of oil in the sump blowing out the gasket there? The bike never sat that long before since i got it together.