firstly there is a disruptor pipe on the side of the exhaust down pipe cut that off and weld over the hole,then there is a brass plate inside the back of the carb pull that out ,take the wedding ring shape washer out from between the two halves of the variator this will give more top end i would also suggest getting some 4.5 gram rollers and putting a 70 main jet in it.of course you could put a typhoon 125 engine in it !
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