MOSCOW—Yuriy Sedykh, a two-time Olympic champion in the hammer throw whose world record from 1986 still stands, has died. He was 66. The Russian track and field federation said Sedykh died early Tuesday following a heart attack. “Deeply mourn the loss of Yuriy Sedykh,” World Athletics senior vice president and pole vault great Sergei Bubka wrote on Twitter. “For me, Yuriy was a friend, a wise mentor.” Sedykh won gold at the 1976 and 1980 Olympics, but missed the 1984 Los Angeles Games because of a Soviet boycott. He returned to win a silver medal at the 1988 Seoul Olympics and won a world title in 1991. Sedykh threw a world record 86.74 meters (approximately 284 feet) at the European Championships in Stuttgart, Germany, a mark that still stands. At this year’s Tokyo Olympics, all 12 finalists in the men’s hammer were born after Sedykh set the record. Sedykh made …