MOPED ARMY

After work I cut the top off the brown filter intake, ran a bit better. Looking at the shit stock exhaust with the crimped small outlet. Took a refrigeration tapered swedging tool and opened up the crimp to a nice round outlet. Revs very nicely now. But I think it still needs a leaner jet than the 78. Gonna try a few smaller ones to see if it improves. Anyone done this to give me an idea of where to start?

Thanks.