cfairweather
CB750 Enthusiast
I recently developed a new tool to check the float levels and this is available on eBay. A plastic plug with rubber hose clamps goes into the large hole on the side of the carb. The clear tubes slide into the clamps and will stay in place unless you pull them out. If you need to adjust the level, turn off the petcock, drain the carb using the tube and remove the carb bowl. Make the adjustment and install the bowl so you can check it again. Makes this task about as easy as it can get. I like to set the levels using the lowest rim edge of the carbs. On the CB750, the lowest edge is closest to the cylinder fins. Simply compare the levels to the lower edge of the rim. The level should not be higher than that edge and about three millimeters below it. You can use a straight edge from the lowest edge or just move a tube over to the lowest edge so you can get a close comparison. I don't recommend starting the engine while using the tool for safety reasons. I also have made visual float level tools for the GL1100 and GL1000.
