All available race results Guillaume Duellens
| Date | Race | Rank |
| Tour de Belgique amateur | ||
| 04/08 | Stage 1 | 27 |
| 05/08 | Stage 2 | 3 |
| 07/08 | Stage 3 | 7 |
Rider information for 1907
| Rank | 806 |
| Score | 0 |
| Name | Guillaume DUELLENS |
| Country | Belgium |
| Team | Individual |
| Date | Race | Rank |
| 10/05 | Bruxelles - Leuven - Bruxelles | 1 |
Rider information for 1908
| Rank | 289 |
| Score | 31 |
| Name | Guillaume DUELLENS |
| Country | Belgium |
| Team | Individual |
| Date | Race | Rank |
| 13/06 | Bruxelles - Les Waleffes | 5 |
Rider information for 1909
| Rank | 555 |
| Score | 16 |
| Name | Guillaume DUELLENS |
| Country | Belgium |
| Team | Individual |
| Date | Race | Rank |
| 25/06 | Championnat de Belgique sur route | 20 |
Rider information for 1911
| Rank | 1393 |
| Score | 0 |
| Name | Guillaume DUELLENS |
| Country | Belgium |
| Team | Individual |