In this project we have performed static & fatigue analysis of crankshaft made of forged steel and Aluminum Alloy (Al 5083) Reinforced with Silicon carbide (Sic material for the purpose of optimization of weight. In this project the material (forged steel) of crankshaft is replaced with developed Aluminum alloy from similar single cylinder four stroke engines. The model of crankshaft is created in CATIA V5 and imported in ANSYS 14 work bench for Static and Fatigue analysis. Analyzed crankshafts are compared in terms of Von misses stress, equivalent strain, total deformation, Fatigue life , Safety factor. Finite element analysis is performed to obtain the variation of stress at critical locations. Mathematical Calculations for various factors are verified by simulations in ANSYS. Results achieved from the analysis are used in optimization of weight of the forged steel crankshaft. The optimization process results in increased fatigue strength, reduction in weight and cost of the crankshaft.