Christian Rayer, a talented rider and experienced developer, paved the way for Yamaha in trial competitions with his 360 prototype in 1972, which served as the basis for the development of the TY 250 production model launched in 1973.
Christian Rayer developed engine kits (175 and 239) with the famous “hedgehog” cylinder head, as well as a swing arm for the 125/175 that was 3 centimeters longer. He also marketed 350 kits for the TY 250, going so far as to homologate, from 1977 onwards, 164 machines that were sold with the “616” type stamped over the “516” of the original 250s.