Hersteller im Baujahr 1921
| ID_manu | year_from | ID | Name | Name | Ort |
|---|---|---|---|---|---|
| 4 | 1.921 | 4 | Harley-Davidson | Harley-Davidson | Milwaukee |
| 34 | 1.921 | 34 | Indian | Indian | Springfield |
| 26 | 1.921 | 26 | Moto Guzzi | Moto Guzzi | Mandello del Lario |
| 3.925 | 1.921 | 3.925 | Triumph (D) | Triumph (D) | |
| 12 | 1.921 | 12 | BSA | BSA | Birmingham |
| 29 | 1.921 | 29 | Z | Zündapp | Nürnberg |
| 8 | 1.921 | 8 | Norton | Norton | Birmingham |
| 305 | 1.921 | 305 | Ardie | Ardie | Nürnberg |
| 101 | 1.921 | 101 | Mars | Mars | Nürnberg |
| 108 | 1.921 | 108 | Gillet Herstal | Gillet Herstal | Herstal |
| 5.095 | 1.921 | 5.095 | Triumph | Triumph | |
| 54 | 1.921 | 54 | DKW | DKW | Zschopau |
| 62 | 1.921 | 62 | NSU | NSU | Neckarsulm |
| 42 | 1.921 | 42 | Wanderer | Wanderer | Chemnitz |