Product Description
Works with 139QMB and GY6 bikes and nearly any 5mm main jet slot CVK carburetor.
Specifications:
- Keihin round-style main jet
 - Thread size: M5x0.80
 - Overall Length: 8mm
 
Compatibility:
139QMB-based 50cc / 80cc engines with the following engine codes:
| 139QMA | 139QMB | 1P39QMB | 1P39QMA-2 | 
| YN139QMB | JJ1P39QMB | 139FMA-2 | BD1P39QMB | 
| BN139QMB | 147QMD | Other QMA models | Other QMB models | 
157QMJ-based 125cc / 150cc / 169cc engines with the following engine codes:
| 157QMJ | 161QMK | 152QMI | 1P61QMK | 
| YN1P57QMJ | 1P52FMI | 154FMI | JJ157QMJ | 
| 1P57QMJ | BN157QMJ | BN161QMK-A | Other QMJ, QMK, and QMI models | 
Don't see your engine listed? If the engine code includes "QM" or "FM" and you're running a 5mm main jet slot CVK carburetor, this product is compatible with your vehicle.