I'm almost finished getting my Puch Maxi Sport MKII up and running. Replaced the spark plug, replaced the petcock, changed fuel line. Put gas into the tank and drained it to make sure the tank isn't clogged. Started it up, and got it going. I took it down the road and it got up to around 27 mph and then it died. I was able to get it to sputter at about 5-10mph all the way back the driveway but everytime I tried to apply the gas it would bog down. It appears to be getting gas, but feels like it's dying because it's not getting gas. At first I realized that the choke was sticking down so after I let it idle for a minute I pull it up. Sitting on the stand she revved like a dream. I let off of the throttle and she died again. The only extra part on the bike is a Proma Circuit Exhaust. Not sure of the jet size but I have a feeling that may need to be checked. What size jet should I have for a ZA50 (2 speed) puch motor with a Proma? Does anyone have an suggestions on how to get it running solid?