07 road king with up grades and dyno at 68 hp why?

i have a o7 road king 96inch.vance & hines true duals big shots with power commander and a spike air intake sys thats should give me 20%more air intake then the stk set up,and was dyno at 68 hp 88 ftlbs torque that doesnt sound good i was expecting bigger gains what could be the problem ?