Now that depends on which bike you have RJ. From what Ive discerned, with the help of the S4 guys the 620 and 900s have a different immobilizer setup. For these bikes you need to replace the ECU, guages, and keys. As the immobilizer process "marries all 3 components together and they cannot be reprogrammed. Now the S4 from what I understand can be reprogrammed with out replacing all of the above mentioned components. You just need to buy keys and you can reprogram the ECU. (Chim in here S4 guys)
I simply solved my lack of key problem by buying and installing an FIM 5.9 ECU and a toggle switch for Off and On. (mine is race only) That was the far cheaper solution for me.