Why does my scooter quit running when I apply weight to the seat?
Starts and runs fine, just when I take off the kickstand, and put weight on the seat it just dies
@theshadows sounds like either a torque issue or you are cutting something off under the seat. Check first to ensure that the fuel line is not being 'pinched' or that it pulls on some wires.
If it idles okay but does not have any torque you do want to check the compression and see if your engine performs as it should. I'd also would try to adjust the carb. You want to start with the air/fuel mixture screw first. Also check your float height and make sure that the level is right and that the needle valve is not stuck.