Moped Army

well the size of your carb isnt the only thing you need to know what jet you wanna use...but it should be marked near the intake side, there will be a number that says something like: "1/12/293" for example. the middle number is how many millimeters your carb is.

if its a stock bike, it will either be a 12mm or a 14mm. if its completely stock, your intake will most likely be marked too, either 12 or 14, but i've had a few that were blank in the circle.