THE EFFECT OF CARBURETOR PORTING AND CYLINDER HEAD PORTING AND FUEL TYPE ON THE PERFORMANCE OF THE JUPITER Z NEW 2010 MOTORCYCLE

On motorcycles with a 4-stroke working system that uses a carburetor system, it basically uses a valve system on the cylinder head. Carburetor porting is to reshape the carburetor inlet or carburetor inlet, it is done so that the incoming air is more and denser during the mixing process with the fuel. Cylinder head porting is carried out by increasing the diameter of the intake and exhaust holes, it is done so that the air and fuel that enters the cylinder space are more aimed at increasing engine performance. Or it can be interpreted so that the engine has more horsepower at the time of suction and more discarding at the time of the discharge step. Before testing the motorcycle, it is necessary to tune up so that it can get better performance during testing. Performance testing is carried out using the dynotes tool in order to obtain accurate data at the time of testing. At the time of testing, before the porting process, the maximum power produced was 8.56 HP with a torque of 6.84 N/m. After the porting process was carried out, a maximum result of 8.96 HP with a maximum torque of 9.08 with the use of pertalite fuel. And in the use of pertamax fuel, the maximum power produced before the porting process of the power produced is 8.73 HP with a maximum torque of 6.95 Nm. In testing using a motor that has been ported, the carburetor and cylinder head can get a maximum power of 8.96 HP with a maximum torque of 7.04 Nm, In the use of pertamax fuel, a maximum power result of 9.17 HP with a maximum torque of 9.08 Nm.