PENGARUH PENGGUNAAN BUSI GANDA DAN CDI GANDA TERHADAP DAYA SEPEDA MOTOR YAMAHA JUPITER Z TAHUN 2009

Purpose of this research is : Investigate influence of use of dual spark plugs against the engine power produced Yamaha motorcycle Jupiter z in 2009, Investigate influence of use of dual CDI against the engine power produced Yamaha motorcycle Jupiter z in 2009, Investigate influence of use of dual spark plugs and dual CDI against the engine power produced Yamaha motorcycle Jupiter z in 2009. Research used experimental methods and techniques of data analysis using analysis descriptive, the results of experiments observed directly then concluded and determine the result of research. Population in research using Yamaha motorcycle Jupiter Z in 2009. The sample in this research is a motorcycle Yamaha Jupiter Z in 2009 with engine number 30C653165 and chassis number F8034661I. Based on the results of the research can be summed up : using dual spark plugs can increased engine power and improve the quality of combustion, brake horse power increased according to the increase according engine round enhancement. Engine round enhancement after the maximum power is reached make power decreases, using single spark plug with dual CDI increased the maximum brake horse power 5.400 HP. Brake horse power enhancement occurring 0.574 HP or approximately 11.89 %, using dual spark plugs with single CDI increased the maximum brake horse power 5.767 HP. Brake horse power enhancement occurring 0.941 HP or approximately 19.50 %, using dual spark plugs with dual CDI increased the maximum brake horse power 5.649 HP. Brake horse power enhancement occurring 0.823 HP or approximately 17.05 %, using dual CDI can increased the maximum engine round, using dual CDI less efficient, multiply the CDI is feared could make shorting the wiring and not necessarily ignition curve between both alike