Tuning parameters of individual wavelength channels transmitted over a multimode optical fiber is provided. Characteristics of the multimode optical fiber used for an optical data link within an optical signal transmission system are retrieved. A wavelength channel grid including each central wavelength in a plurality of central wavelengths that corresponds to each particular wavelength channel in a plurality of wavelength channels used to transmit data via optical signals over the multimode optical fiber is determined. A maximum allowable data rate is calculated for each wavelength channel based on the characteristics of the multimode optical fiber at defined channel wavelengths, optical signal transceiver specifications, and data transmission performance requirements for the optical signal transmission system. Operational parameters are assigned to each wavelength channel based on the calculated maximum allowable data rate for each wavelength channel to achieve the data transmission performance requirements for the optical signal transmission system.