I just got a 79 yamaha xs1100 today that needed a new battery, gas, and new tires. Got the battery in and bike running with limited difficulty, but my buddy was sitting on it and revving it in neutral. Besides from the exhaust popping from time to time it was running smoothly. He really laid on the gas and got it up to about 5,000 rpm in neutral when it acted like it ran out of gas and then when he turned it off I noticed that oil started leaking out of the side pretty heavy. Any ideas on what this might be? Looked as though it was coming from the left side of the bike. Not too familiar with bikes so I can't be all that more descriptive.