Engine flooding

Right,
after some fetling, the fuel pressure regulater appears to be fine, hopefully, however, I checked voltage at the injector connectors and found that 3 and 4 have voltage and appear to be operating correctly. On 1 and 2 however, there is no voltage even when cranking the engine over. Checked my wiring diagram and it shows that 2 cables coloures white and red from the injectors go to the relay, and then they go off to the ecu. But is confusing as  the diagram shows that all these cables splice together in the loom. I can't believe that there may be break in the cable. This bike has done little milage and hasn't been played around with, and I can't see any evidence of rodent damage. So wondering if the relay is at fault.

If the in loom joint is anything like the in loom joint of multiple earth's on 650's then nothing can be overlooked.
Under the loom wrapping on 650's 3 earth's join three in one out. The joint is simply 3 bare striped wires stuffed into one end of a brass tube with a single stuffed in the other tube end then just crimped. Not soldered or connectors. 
Every one I've seen has been green with corrosion and had massive resistance and need doing  properly using connector blocks. 
Unless you have striped all the sheathing off you can't take anything for granted on a 40 yo wiring loom. 

Every vehicle has dozens of these "node" connections in the loom and all suffer with corrosion when the damp has gotten into it regardless of mileage. The below is my solder in solution