Starting from the beginning. What all have you done to this bike? List any and all mods or changes. If it did not have this problem and now does. It's got to be in there somewhere. Or the wrong combination of things.

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