hey i had the same problem get one of the online manuals and a pocket tester and first test the cdi magneto if that's good just keep testing everything else i had the same problem turned out to be the spark plug cap but ya if u get urself a manual it'll tell u what the tolerence is on each part and wire and if it's out usually u have to get a new one
Well it probablly whasnt your "CAP" per say. More likely it was your Ignition coil.
Do a search on here, for "Ignition coil" or threads that I have replied too. theres a step by step write up I did that will tell you how to test everything.