Instead of bending the tang, I made a simple float support & would flex the tang X number of times, then re-check the fuel level.
I also made a simple carb stand and used a large funnel & tubing as the fuel supply.
Also, just use 1 or 2 screws on the float bowls >> that should save some time.
I checked the KZ400.com technical specs page but didn't see the float height for your motorcycle.
However, there is a carb setting page for the 77 400-D4. see link below. I may have overlooked the info for your model.
Warning: the KZ400.com Forums may harm your computer. someone else said they were harmful, so I don't go there.
KZ400.com >> Technical tips workshop manual section >> Adjusting 1977 KZ400-D4 carburetors
I assume the float level is taken from the gasket mating surface w the gasket removed. ???
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