Pion production in dAu and AA' collisions at RHIC energies shows a suppression at intermediate-p_T region in the forward rapidities. In the case of dAu collisions this can be explained by conventional nuclear shadowings. Our theoretical calculations displayed, this suppression moves to the higher-p_T range at backward rapidities. In AuAu collisons shadowing related suppression effect superposed by jet-quenching. Both effects cause a strong suppression in the nuclear modification factor. I will investigate and compare nuclear modification factors for pion production in dAu, CuCu and AuAu collisions at RHIC energies at higher rapidities.