72cc BBK, jet question

[Zappa]

Originally Posted by peonpete

Hi guys, i put a 72cc kit into my scooter about a month ago and besides that everything is stock. It surprisingly runs great with the stock setup and gets up to 37mph against the wind and 40ish with the wind at my back [im 220lb]. Now, i do want to up jet the carb for more performance. I have a kit that has a 80, 82,85,88 and a 90 jet.

I would like to take the air restrictor out of the stock airbox for more airflow and use a jet with it.

OR

I am willing to buy a free flow air filter and couple that with a jet.

If i could get some opinions on what jet to use for both options i would really appreciate it.

I know this is from last October, but I just joined a few days ago and noticed there was no followup, so not sure if you got your answer. You didn't specify if you are running a two or four stroke engine. I just did a 72cc cylinder and performance kit on a 2002 Zuma and I'm working on the tuning right now. The stock jet was a #80, my jet kit goes up to #120, but after doing some research, I started with a #95. I ran it with no air filter and noticed a big improvement in power and speed, that was until I put the stock air box back on, then it wouldn't get up to speed. I took the restrictor out, but it didn't make a difference, so I replaced it with an aftermarket K&N style filter and the power came right back. It still bogs a bit in the mid range and I think I have a fuel flow problem, but the plug was a nice tan color showing me it's burning well.