Jakarta
Chopra's gold is India's only second medal in javelin throw in Asian Games history after Gurtej Singh won a bronze in 1982 in New Delhi.
The 20-year-old's wining threw came in his third attempt. He began with 83.46m and fouled the second attempt.
Liu Qizhen of China was a distance second with a best throw of 82.22m while Pakistan's Arshad Nadeem won the bronze with an 80.75 effort.
The Commonwealth Games and reigning Asian champion completely dominated the competition as he bettered his own national record of 87.43 which he had come up with in Doha during the first leg of the Diamond League series in May. None of the competitors in the field had a 85-plus throw this season.
Chopra's biggest rival was expected to be Chao Tsun Cheng, who last year recorded a throw of 91.36m but the Chinese Taipei thrower could manage a best of 79.81 to finish fifth.
Chopra, the world junior record holder of 86.48, has been in tremendous form this season as has consistently crossed the 85m mark.
He won the Federation Cup in March with 85.94m, clinched a gold in the Gold Coast Commonwealth Games with a throw of 86.47m, before the 87.43 effort in Doha. Before coming here, he had 85.17 and 85.69 in France and Finland during his preparations for the Asian Games.
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