This is just my opinion about why not to remove Secondary's. I heard that you lose power when removed, because the secondary's injectors hit the butterfly that have an angle so the fuel when hit the butterfly flow to the head and when you remove them and the secondary injectors start to work as they have a 90 degree angle or more (compare to primary injectors) the fuel hit the throttle body and makes a turbulence that make you lose power. I was thinking in remove mine but when I looked at the K8 service manual page 228 section 1D-9 I changed my mind. And the zx14 only have one set of injectors (4) and the busa two set (8). I think if there is any how to change their position like lower ones you will have better flow and a possible HP gains. I’m just guessing because I’m a beginner in performance but I like to read and heard other experienced mechanics. Hope someone is agree with me.