As the title states, How do you tell a big bore jug from stock? I am replacing my carb with a 34mm PJ. I am trying to get a ballpark to set my jetting to. As we all know when replacing a small carb with that of an oversized unit, you have to modify your reeds. I have bored my VF3 that fits into the intake. While I had it off I noticed that intake ports looked really big. I will also take a closer look at my piston to see if it is forged. So back to my main question... How can I be 100% positive that my jug is a big bore jug without tearing the top end apart? Also jetting advice for an 03 Blaster with CFM airbox w/foam UNI, Keihin PJ34, FMF pipe and silencer, 30-50ft elevation. Has: 150m, 48p, 3slot.