155 main jet?

[Usafdolfo16]

First post!! And it's a problem lol =(

I have a 2008 150cc gy6 sunl that has about 300 miles on it. The scooter runs great with no errors stock. I recently installed a free flow exhaust and performance air filter so I knew I had to change out the main jet. The stock one was a 105 and the spark plug was bone white. So I installed a 125 jet and now the scooter can get up to 57 mph but bogs when I gun the throttle quickly then starts up again. Feels like I loss the start speed a lot. So I took out the carb (and by the way it's a new carb) and installed a 135 jet and it felt a little better but not really. Took out the plug and it was a little less white. Had a dark spot that was almost made it look dirty and Not brown. I know I was running lean since I got the muffler installed first and ran the scooter and my muffler tip caught on fire from being so hot.....Maybe Im getting too much air with the new filter or do I need to up jet to 155? Don't know what to do. I live in Las Vegas so 2000ft ish elevation. Please any one help!