Great info,thank you! I already welded up a straight pipe,and had no power/speed increase from it. I’ll try a 22mm carb like you suggested. Maybe that and the pipe together will give me a tad more. I’d love to see a 212cc predator engine on one of these Phatmoto bikes instead of that 79cc Lifan engine. I just want to see somebody do it first so I have something to follow along to.