Valve Cover Port???

[RyanosAlien]

I bought the scooter from a guy in peices so all vacuum lines and parts were disassembled but I managed to get it half way going good over the pass week, I ran the valve cover vacuum up to the intake and set the valves to .005 for both intake and exhaust, the air filter and box was junk so I threw on a off brand filter and oiled it and the main problem I'm having is since I wasn't the first owner I don't know what all the added to it, like I noticed on the needle in the float bowl there is 2 little spacers and undle full throttle it still likes to sputter and bog down granted adjusting the valves helped a lot but still feels like theres some thing I'm missing, I'm now looking into how elevation works with the carb I'm at 850 feet elevation and trying figure out do I need to go ahead and reject or what???? Lol it's a pain in the ass

P.S: This is my first scooter and it's a 2006 chau longbo LB150-19 150cc alien edition/name and I'm having trouble finding info on it especially what was standard equipment.

[Gene563]

I'm new here, but I have been doing a lot or research.
If you replaced the stock air box with a performance filter, you may be running to lean now at full throttle. A lot of people are running a #115 main jet with the cone type filter. You might try the old box and filter as a test and see if it smooths out.