I have '98 kawasaki vulcan that was running well until it sat for over 2 months. After sitting, it would not start up, and I found that the float had been stuck open in the carburetor. The engine was getting very flooded with gas, and after getting the float free in the carburetor, I changed the spark plugs and oil. When I tried to start the bike again, it would fire and sound alright for about 10 seconds, and then it would start to die. When I open the throttle, the engine starts to rev up, but then it will stop and go back towards the idle, before it dies. Each time I try to start it after it dies, it becomes harder to get the engine to fire. I think that the most likely cause of the problem is that the float level on one or both carbs became off when I was cleaning and freeing them up. I was just wondering if anyone else has had a similar problem, or if this sounds like the float levels on the carbs are uneven or off. Thanks for any help or advice.