From 1934 to 1936 Willi Oberbeck represented the German national amateur cycling team. During this period Oberbeck achieved several podium finishes at local races and was named as an alternate for the road race at the 1936 Berlin Olympics. By 1937 he had turned professional, riding in several editions of the Deutschland Tour. Oberbeck had his biggest result in 1938, wining the opening stage of the Tour de France and wearing the yellow jersey for the next day. He continued to race for a few more years before retiring in 1942.