The forward only conversion kit makes Revo legal for racing where reverse is not allowed. It reduces the internal rotating mass in the transmission for quicker acceleration and provides a small, additional weight reduction by eliminating the OptiDrive module, and the micro servo and linkage. When the transmission is fitted with the forward only conversion kit, the weight of the transmission is reduced by either 61 grams (when using the aluminum output shaft) or 48 grams (when using the optional steel output shaft).