Big Bore Kit
This kit has what you need to get overall better gains on both ends. I also bought the 17.5 carb and electric choke kit. After seeing the gain with big bore, decided not to install the carb as there was going to be multiple modifications that needed to be done. Stay with the Big Bore Kit although install the set of reeds to get air and fuel you need. I installed on zuma 08, you do not need the shim the block, just use the gasket, I did thread test and for mine you dont need the shim.