I've just been reading about your problem - I've got an '86 Aero which did exactly the same and had to replace the fuel pump points - if you look at ebay item 380316987123 this is the kit - stopped my bike flooding instantly as the points were jammed in the 'pump fuel' position. Its called a 'Fuel Pump Repair Kit Honda CBR NTV VT XRV' and the points are at the back of the pump unit under the plastic cover.

A quick test for this is to put a mole grip or something similar on the fuel pipe between the fuel pump and the inlet of the carbs - this should imitate the carb bowls being full and the pressure shutting down the pump. Mine would continue pumping even with a clamp on the fuel line which was flooding the carbs.

Hope that helps...