The developments in automotive field followed by the human need for transportation. There are various kinds of transportation in Indonesia such as motorcycles. The ignition system on the motorcycle plays an important role as a regulator in the process of combustion of fuel and air mixture in the cylinder at the last step of compression. There are several components of ignition on the motorcycle namely CDI (Capasitor Discharge Ignition), coil (ignition coil), and spark plug. The improvements of ignition systems are considered to improve engine performance and fuel consumption of motorcycles. The Testing has been done by using Motorcycle HONDA Supra-x 125 4 Step 125 cc Year 2007. It was done by conducted characteristic influence of variation of Standard CDI and Racing CDI, standard spark plug and iridium spark plug, and fueled Pertamax turbo. It was conducted by using a test tool of spark plug, dynotest, and road test. The result of this research showed that the performance of torque engine and the most optimal power on the test of four-cylinder 125 cc engine with Standard CDI, BRT I-Max CDI, standard spark plug NGK CPR6EA-9 and Denso Iridium Power fueled Pertamax turbo, the highest torque on variations of BRT I-Max CDI and iridium spark plugs, ie 12.58 NM at 4862 RPM. The power of 10.3 HP at 6913 RPM engine speed. Because the use of racing CDI produces larger and more stable sparks due to high electric currents and spark sparks which focus on a single point from the standard, so it speed up the combustion process, and mepping on the appropriate I-Max BRT CDI.