Debutants
Takahiro Koyama is the youngest debutant in National Championships Japan MU23 - ITT in 2015. There are 6 debutants.
| # | Rider | Team | Age |
|---|---|---|---|
| 1 | KOYAMA Takahiro | Shimano Racing Team | 18y + 205d |
| 2 | ONODERA Rei | Nasu Blasen | 19y + 291d |
| 3 | ARASHIRO Yudai | Nasu Blasen | 19y + 353d |
| 4 | AMEZAWA Takeaki | Nasu Blasen | 20y + 137d |
| 5 | KISHI Takahito | Gunma GRIFIN Racing Team | 21y + 104d |
| 6 | KOISHI Yuma | CCT p/b Champion System | 21y + 279d |