Before revision:  Rev. E {\bf 75}, 041905 (2007)}] by incorporating processes which correspond to shifting of the motor proteins from one protofilament to another. On the basis of analytical treatment of our model, we predict the effects of lane changing on the flux of the KIF1A motors .
After revision:  Rev. E {\bf 75}, 041905 (2007)}] . By carrying out analytical calculations and computer simulations of this extended model, we predict the effects of lane changing on the flux of the KIF1A motors .