what shims if any are you using with the NBZTs? each shim (.5mm) is like adding a size to the main jets. So if you have shims, take them out, leave the pilots alone. Or if no shims drop a main jet size and leave the pilots. That way you keep the needle profile and change the volume around it.

05 speedmaster - 1100cc, 11:1 racing pistons, Carillo rods, thunderbike cams, ported and polished head, 2mm over intake and exhaust valves, Barnett kevlar clutch, scepter pipes, oversize manifolds, 45mm HSR's, TTP stage 4 firestarter