I have a 1970 CT70 HK0 that I am having spark problems with. I am not a good Mechanic but am learning and enjoying working on this one. I replaced points and condenser, coil and plug. I tested spark with a voltage probe that lights up and a meter. The probe lights up at the output wire from the mag and at the input to the coil but not at the plug cap. I do show a bit over 100 vac at the cap but plugs will not fire. HELP.