Moped Army

hey all -
its that time of year for help questions --

Puch maxi luxe idling, but slowly. When I give it gas it dies - expecially if the engine has to put out more power (like up a small incline or starting off with a rider)

I dont know what to mess with - there is fuel, spark and air coming in, but i dont know which is messed up and causing the loss of power - carb intake is clean, the engine is just really weak, no power!

thanks in advance for any repair tips
matt