I just completed repairs on an oil leak (replaced head gasket, leak stopped) and, when I put everything back together, I have one unknown tube fitting. There is a small black box located under the radiator. There are three tube fittings on the box: one is labeled "vent" (yellow dot), one is labeled "surge" (green dot) and one is either not labeled or the label has worn off. I THINK I have the correct tube on the "surge" fitting and I THINK I have the correct tube on the unlabeled fitting. I do not have a 3rd tube for the "vent" fitting. I started the bike, it ran great during my 15 mile test run yesterday. The only unusual event was that it acted like it was running out of gas with about 1/5 of a tank of gas. I filled the tank and it ran great. I went to start the bike this morning and it wouldn't "turn over". When I turn the key, it sounds like the motor turns over half way, then stops abruptly. I think the battery is fine. Could this be a "vapor lock" issue if I have put the tubes on the wrong fittings? Maybe one of the tubes needs to be on the fitting labeled "vent". My service manual does not show this black box. I was not able to work on the bike this morning as I had to get to work. Any thoughts before I start to diagnose this issue.