I have a 2017 500cc Bullet Classic. Have had 2 fuel injector replaced and still had problem with injector. Ive been told that the plug and play EFI which i have put in the 2nd with out any help. Now I have change over to Amil ! carb kit and removed everything except the 2nd EFI and it ran for about 2k miles. It looses spark to no spark . Lots of fouled plugs. Even with the gap at 70 to 80 as . I feel your pain and I think you will find that this bike a a lemon for fuel injection and the brain box telling it to inject. It seems when it does it dumps too much fuel and and covers the plug until fail. Does any of this sound fimiliar. ???