Stock carb that can be jetted please choose 155 for GY6 150 and 95 for GY6 50
Also used on 85cc GY6 upgraded 50cc engines. You will need a new intake plus manifold spacer to get this carb tuned in on an upgraded 50. I do have spacers and complete upgrade kits for 70/80/85cc GY6 50 139QMB engine upgrades..you can choose a CVK carb kit of flatslide carb kit