This paper presents a modeling method for an experimental two-link flexible manipulator that incorporates experimental data to improve model accuracy.The manipulator system is modeled by using the Euler-Lagrange equations of motion together with a modal approach. After obtaining a closed-form model, the mode shape parameters were modified based on the fact that the generalized mass matrix M has to be positive definite and that the predicted natural frequencies of the linearized model have to agree with the experimental results. Some experimental validation results are provided in this on-going work.