I have this problem with a fuel pump. It sometimes works, sometimes not. I turn the key, dashboard hands held, relay on/off, but the pump does not prime/pressure. I do not anything with a bike, even not move, I do it after 10min, pump works. It always allows me to try to start the engine, when pump works, it fires, if not, of course it not fires.
Five times it went down while riding. Turn the key about free times, it goes again.
It works one week without trouble, next three days every second key turn does not start the fuel pump. So the trouble comes at random. That´s the worst thing. Unfortunately, it always works at the workshop, so finding the problem for example in wires is very difficult.
I changed fuel pump and fuel filter, battery, switching relay, ECU, check other relays, fuses, voltage, everything OK and it is still the same.
Has anyone experience like this? I read a lot of threads, but nothing like this. I know one more person nearby, who has the same problem (also did not solve yet), so I think it should be known.
Thanks for every idea,