Your right on the most part. Smaller carbs have faster air flow, so they pull more fuel out of the jets. HOWEVER, I've dynoed 28mm,33mm,34mm, and 35mm keihin carbs on my 4 mil shee...All 4 sizes liked the same main jet size. Ironic but true. The larger the carb, the more power increase. I actually gained more bottom end, then top end w/ the 35's...So when people say larger carbs only give you topend. Its not true. A properly jetted carb will gain all around if sized right. Good luck. 162 mains, DEJ needles on the 3rd clip, 48 pilot.