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1993 Katana 750

Hey guys, some of you may have happened to catch my last post where I was saying my bike was running like crap and cyl. 1 and 4 werent firing. A full carb. rebuild endeavor got big bird running at 100% again.

The new problem is that when the bike sits for a few days, it somehow floods the motor to the point where it hydro-locks itself. This is where I have to bump it back and forth in gear to free it up a little, and it eventually will turn itself over, start and blow a white mist of gas exhaust out the tail end. I must have left a needle open or something when I rebuilt the carbs???

What I did exactly was take everything apart, hit it with carb cleaner and carefully blow it all out with compressed air. I was very careful not to damage or neglect to put back any seals or O-rings. Also while in there I replace many of the O-rings that sealed the floats to the carb base because someone had previously replaced half of them with ones that were far too big, which was half of my original problem. What do you guys think, something still stuck open?? (FYI this happened once before I rebuilt them and carb #2 had gas coming out the front of the mouth as well as flooding the motor) Thanks for any input

Sounds like you have a float or two that is sticking and allowing fuel to continually flow into the carbs.

I agree. Either a float(s) is sticking, or you left the float level to low when you reassembled the carbs. In the short term, you can stop the hydrolocking by turning the fuel tap off when you park the bike.

If your fuel tap has no "off" position, and has a vacuum line running to it, then you probably also have a damaged diaphram in the the petcock. Vacuum operated petcocks should not allow fuel to flow to the carbs unless A) the engine is running. or B) The petcock is set to the "prime" position.

I do have a valve on the side of the tank, I guess i'll just close it off for now. thanks