Hi, good little bike, you dont say in what speed range you get this mis-fire, even gearbox problems can sound like the engines mis-firing. Anyway, did you test the old coil then?? have you checked/re-set the ignition timing after cleaning points? The points faces should be square & have no pitting or burning marks. Its always worth fitting a new plug and making sure its the correct grade & has the correct electrode gap. I think your new coil will have the HT lead already attached,and the plug cap's a good tight fit, we can discount problems with the HT lead!
Unless there's an electrical fault elsewhere you could check the carb floatbowl for muck & check all jets are clear. hope that helps.
2 stroke Ted
April 2010
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