I've been fiddling with the carburetor jets for a couple weeks and not getting my scooter to run smoothly. I then read on ScootDawg about intake tube diameter and length to setup pressure waves and how often they run better with the stock air box. I have been disappointed at the increased noise with LESS performance. so I put the stock air box back on. I removed the inner snorkel and outer snorkel to give it a little more free flow. It's quieter, and is running happily with no skipping on the 115 jet (stock was 105). No big loss, I paid about $15 for the high-flow air filter and pre-filter.
I also changed out 3 of the 6 rollers to 11g (stock is 12.8), losing about 6g. Haven't noticed any difference there yet. I'll give it a few days, tweak the carb a bit, then try some other weights and/or the torque spring.