Latest problem (grrrr

Out for a ride and bike just stops. Turns out to be a fuel issue
Pull pipe off carbs and turn engine over and no fuel coming out of pipe.
Put meter across bike side of fuel pump connector and get ~6. v
OK so buy a new pump from eBay, connect it up but same problem

Check cable bike side again, turn engine over and still getting a reading. I then connect the pump (new or old doesn't matter) and put the meter across the pump side connector (by inserting the meter probes down into the plastic alongside the cable). Nothing
Now I certainly have very limited skill with the electrical side of things but to my mind if I get a reading with the pump disconnected surely I should also get a reading with a pump connected from the pump connector?
Thanks for your thoughts...