[4][5] At the 2000 Summer Olympics in Sydney, Kim decided to experiment with the sprint freestyle, competing only in two swimming events.

[8] Two days later, in the 50 m freestyle, Kim missed the semifinals by a small fraction of 0.02 seconds, finishing a tie with China's Jiang Chengji in a South Korean record of 22.82.

[9] When his nation hosted the 2002 Asian Games in Busan, Kim won a total of two medals, one gold and one bronze.

In the 50 m freestyle, Kim was delighted and overwhelmed by the home crowd, as he shared a gold medal with Uzbekistan's Ravil Nachaev in a matching time of 22.86, just 0.04 seconds outside his record from Sydney two years before.

[10][11] He also captured a bronze, along with his teammates Sung Min, Han Kyu-Chul, and Ko Yun-Ho, in the 4×100 m freestyle relay (3:23.58).