[3] In 2012, she watched the London Olympic men's team sprint on TV by chance, was immediately attracted to Girls Keirin and resolved to aspire.

[6] On January 24, 2014, Yuka Kobayashi won the Keirin race at the Japan Track Cup and placed second in the sprint.

[7][8] Yuka Kobayashi and Takako Ishii placed 10th in the Olympic Sprint at the 2014 UCI Track Cycling World Championships.

[11] On May 16, 2014, she celebrated her debut as a professional keirin cyclist on the Kishiwada Velodrome and won against the second placed Mashimo Ruruko with a distance of six bicycle lengths.

Her winning streak of 17 consecutive victories broke the former record for female keirin pros in Japan.

At the Japanese Track Cycling Championships in April 2015, she won the Team Sprint, scored second in the 500 m time trial and third in the Keirin race.